Machine-readable diagnostic test devices and methods and apparatus for making and / or processing same

Abstract

Methods, apparatus, systems, and articles of manufacture for fabricating and / or processing diagnostic test devices are disclosed. An exemplary apparatus includes a sensor for measuring a current between first and second electrodes of a bioelectrochemical cell coupled to a test zone corresponding to a target analyte on a porous medium of the device, a processor for comparing the current to a threshold and identifying the presence of the target analyte in the sample if the current exceeds the threshold, and an antenna for wirelessly transmitting the result.

Description

[Technical Field]

[0001] Related Applications This patent claims priority to U.S. Provisional Patent Application No. 63 / 129,375, filed December 22, 2020, and U.S. Provisional Patent Application No. 63 / 032,093, filed May 29, 2020. U.S. Provisional Patent Application No. 63 / 129,375 and U.S. Provisional Patent Application No. 63 / 032,093 are incorporated herein by reference in their entireties.

[0002] FIELD OF THE DISCLOSURE The present disclosure relates generally to biosensors, and more particularly to machine-readable diagnostic test devices and methods and apparatus for making and / or processing the same. [Background technology]

[0003] Biosensors (e.g., lateral flow devices such as lateral flow assays (LFAs)) are devices that can detect conditions, diseases, etc. in humans or animals based on a sample from the human or animal (e.g., a blood sample, saliva sample, urine sample, etc.). LFAs are used to detect the presence of target analytes to determine pregnancy, the presence of HIV, the presence of Ebola, the presence of various toxins, etc. [Brief explanation of the drawings]

[0004] [Figure 1A] 1 is an exemplary environment including an exemplary machine-readable lateral flow immunoassay generator for generating machine-readable lateral flow immunoassays as described in conjunction with the examples disclosed herein. [Figure 1B] FIG. 1B is a side view of the exemplary machine-readable lateral flow immunoassay of FIG. 1A. [Figure 2A] 1B shows an exemplary implementation of a portion of the machine-readable lateral flow immunoassay of FIG. 1A. [Figure 2B] 1B illustrates an alternative exemplary implementation of a portion of the machine-readable lateral flow immunoassay of FIG. 1A. [Figure 2C]1A, 1B, 2A, and / or 2B show an exemplary design of any one of the potentiometric and / or bioelectrochemical cells. [Figure 2D] FIG. 1B shows a top view of an alternative exemplary implementation of the machine-readable lateral flow immunoassay of FIG. 1A. [Figure 2E] FIG. 2D shows a side view of the machine-readable lateral flow immunoassay of FIG. 2D. [Figure 2F] 2D-2E show exemplary conjugates that can be attached to antigens and / or antibodies immobilized on the test line of the machine-readable lateral flow immunoassay. [Figure 2G] 2D-2E show exploded views of the exemplary lateral flow immunoassay of FIGS. 2D-2E within an exemplary housing. [Figure 2H] 1 shows an alternative exemplary machine-readable lateral flow immunoassay comprising quantum dots. [Figure 2I] Figures 1-2H show different implementations of front-end channels that can be used in machine-readable lateral flow immunoassays. [Figure 2J] Figures 1-2H show different implementations of front-end channels that can be used in machine-readable lateral flow immunoassays. [Figure 2K] Figures 1-2H show different implementations of front-end channels that can be used in machine-readable lateral flow immunoassays. [Figure 2L] 1-2H show bottom views of the housing for the machine-readable lateral flow immunoassay of FIGS. 1-2H, including an exemplary housing lid and an exemplary switch in a first position. [Figure 2M] 2K shows a bottom view of the housing for the machine-readable lateral flow immunoassay of FIG. 2L with the exemplary switch in a second position. [Figure 2N] 2L shows a cross-sectional view of the housing of the machine-readable lateral flow immunoassay with the switch in a first position and the exemplary electrode substrate in a first position. [Figure 2O]Figure 2L shows a cross-sectional view of the housing of a machine-readable lateral flow immunoassay where the switch is in the second position and the exemplary electrode substrate of FIG. 2N is in the second position. [Figure 2P] Figure 1-2H shows a perspective view of the housing of a machine-readable lateral flow immunoassay with an alternative exemplary switch. [Figure 2Q] Figure 2P shows an internal view of the housing of a machine-readable lateral flow immunoassay with an exemplary switch in the first position, which is a partial cross-sectional view taken along the Q-Q line of FIG. 2P. [Figure 2R] Figure 2P shows an internal view of the housing of a machine-readable lateral flow immunoassay with an exemplary switch in the second position, which is a partial cross-sectional view taken along the R-R line of FIG. 2P. [Figure 3A] Figure 1A shows an alternative exemplary machine-readable lateral flow immunoassay that can be generated by an exemplary machine-readable lateral flow immunoassay generator. [Figure 3B] Figure 3A shows an exemplary circuit completion and silver amplification process that can occur in an exemplary machine-readable lateral flow immunoassay. [Figure 4] Figure 1A is a block diagram of the implementation of a machine-readable lateral flow immunoassay generator. [Figure 5] Figure 1A, 1B, 2A, 2B, 2I-2K and / or 3A is a block diagram of the implementation of a wireless chip on a machine-readable lateral immunoassay. [Figure 6] Figure 1A is a block diagram of the implementation of a machine-readable lateral flow immunoassay reader application. [Figure 7] Figure 1A and / or FIG. 4 shows a flowchart representing machine-readable instructions that can be executed to implement a machine-readable lateral flow immunoassay generator. [Figure 8A] Figure  1A, 2A, 2B, 2I-2K, 3A, and / or 5 shows a flowchart representing machine-readable instructions that can be executed to implement a wireless chip. [Figure 8B]1A, 2A, 2B, 2I-2K, 3A, and / or 5 shows a flowchart representing machine-readable instructions that may be executed to implement the wireless chip of FIG. [Figure 9] 1A, 2A, 2B, 2I-2K, 3A, and / or 5 shows a flowchart representing machine-readable instructions that may be executed to implement the wireless chip of FIG. [Figure 10] 1A, 2A, 2B, 2I-2K, 3A, and / or 5 shows a flowchart representing machine-readable instructions that may be executed to implement the wireless chip of FIG. [Figure 11A] 1A and / or 6. FIG. 1B shows a flowchart representing machine-readable instructions that may be executed to implement the machine-readable lateral flow immunoassay reader application of FIG. [Figure 11B] 1A and / or 6. FIG. 1B shows a flowchart representing machine-readable instructions that may be executed to implement the machine-readable lateral flow immunoassay reader application of FIG. [Figure 12] FIG. 8 is a block diagram of an exemplary processing platform structured to execute the instructions of FIG. 7 to implement the lateral flow immunoassay generator of FIGS. 1A, 1B, and / or 4. [Figure 13] FIG. 12 is a block diagram of an exemplary processing platform configured to execute the instructions of FIGS. 8A-10 to implement the wireless chip of FIGS. 1A, 2A, 2B, 2I-2K, 3A, and / or 5. [Figure 14] FIG. 11B is a block diagram of an exemplary processing platform structured to execute the instructions of FIGS. 11A-11B to implement the machine-readable lateral flow immunoassay reader application of FIGS. 1A and / or 6. [Figure 15]FIG. 11A is a block diagram of an exemplary software distribution platform for distributing software (e.g., software corresponding to the exemplary computer-readable instructions of FIGS. 11A-11B) to client devices, such as consumers (e.g., for license, sale, and / or use), retailers (e.g., for sale, resale, license, and / or sublicense), and / or original equipment manufacturers (OEMs) (e.g., for inclusion in products distributed to retailers and / or direct purchase customers, etc.). DETAILED DESCRIPTION OF THE INVENTION

[0005] The figures are not to scale. Alternatively, the thickness of a layer or region may be exaggerated in the figures. Generally, the same reference numbers are used throughout the drawing(s) and accompanying written description to refer to the same or similar parts. As used in this patent, saying that any part (e.g., layer, film, area, region, or plate) is in some way above (e.g., positioned, located, disposed, formed, etc.) another part indicates that the referenced part is either in contact with the other part or is above the other part with one or more intermediate part(s) located therebetween. Connected references (e.g., attached, coupled, connected, joined, etc.) should be interpreted broadly and may include intermediate members between and relative movement between an assembly of elements, unless otherwise indicated. As such, connected references do not necessarily imply that the two elements are directly connected and in a fixed relationship to each other. Saying that any part is "in contact" with another part means that there are no intermediate parts between the two parts. Although the figures show layers and regions with smooth lines and boundaries, some or all of these lines and / or boundaries may be idealized. In reality, the boundaries and / or lines may be invisible, indistinguishable, and / or uneven.

[0006] Rapid diagnostic tests include biosensors or test strip devices (e.g., lateral flow immunoassays (LFAs)), which include a first area for obtaining a sample (e.g., blood, urine, saliva, etc.) and a second area for changing (e.g., changing color and / or undergoing another change in physical properties) if a target analyte corresponding to a particular disease or condition is present in the sample. For example, a user applies a sample to the sample pad of a test strip device, or simply a "test strip" (e.g., an LFA, etc.). Upon application, the sample migrates along the test strip to a conjugate pad containing a conjugate (e.g., a detectable label, tag, linker, antibody, antigen, etc.) specific to the target analyte. If the sample contains the target analyte, a reaction (e.g., a chemical reaction, a biochemical reaction, a physical reaction, etc.) occurs on the conjugate pad, and the target analyte binds to the conjugate. The test strip also includes a test line, which contains molecules (e.g., immobilized antibodies, antigens, analytes, aptamers, etc.) specific to the target analyte that bind to the first set of conjugate molecules (e.g., probe molecules) from the conjugate pad. For example, if the analyte of interest is an antibody, the positive test area contains an immobilized antigen. If the analyte of interest is an antigen, the positive test area contains an immobilized antibody. The label or conjugate contains a first binding moiety capable of binding to the analyte of interest and, in some instances, a second visualization moiety. Thus, when a sample (e.g., containing a bounded target analyte) flows into the test zone (e.g., the reaction zone), the antibody, analyte, or antigen at the test line binds to the bounded target analyte, thereby immobilizing the target analyte. In some test strips, the immobilization of the target analyte produces a visible output that identifies the presence of the target analyte in the sample. Thus, a scanner or user can identify whether a target analyte (e.g., corresponding to a condition or disease) is present in the sample based on the color of the test zone.

[0007] "Target analyte," "analyte," or "analyte of interest" refers to a compound or composition having at least one epitope or binding site to be detected or measured in a sample. An analyte can be any substance for which a naturally occurring analyte-specific binding member exists, or for which an analyte-specific binding member can be prepared. Analytes include, but are not limited to, toxins, organic compounds, proteins, peptides, microorganisms, amino acids, nucleic acids, hormones, steroids, vitamins, drugs (including those administered for therapeutic purposes and those administered for illicit purposes), and / or metabolites of or antibodies to any of the above substances. The term "analyte" also includes any antigenic substance, hapten, antibody, macromolecule, and / or combinations thereof.

[0008] "Label" refers to any substance capable of producing a signal detectable by visual and / or instrumental means. Various labels suitable for use in the examples disclosed herein include labels that produce a signal through chemical and / or physical means. Examples include enzymes and substrates, chromagens, fluorescent compounds, chemiluminescent compounds, colored or colorable organic polymer-based latex particles, liposomes, and / or other vesicles containing directly visible substances. In some examples, radioactive labels, colloidal metal particles, and / or colloidal non-metallic particles are used. In some examples, labels include colloidal gold and latex particles.

[0009] "Labeling agent" or "conjugate" refers to a substance comprising a detectable label attached to a specific binding member. The attachment can be covalent or non-covalent and can involve nucleic acid hybridization. The label enables the labeling agent to produce a detectable signal that is directly or indirectly related to the amount of analyte in the test sample. The specific binding member component of the labeling agent is selected to bind directly or indirectly to the analyte.

[0010] "Specific binding member" refers to a member of a specific binding pair (e.g., two different molecules, one of which specifically binds to the other by chemical or physical means). Where the specific binding member is an immunoreactant, it can be, for example, an antibody, an analyte, an antigen, a hapten, or a complex thereof; where an antibody is used, it can be a monoclonal or polyclonal antibody, a recombinant protein or antibody, a chimeric antibody, a mixture(s) or fragment(s) thereof, and a mixture of an antibody and another specific binding member. Specific examples of specific binding members include biotin and avidin, an antibody and its corresponding antigen (both independent of the sample being assayed), a single-stranded nucleic acid and its complement, etc.

[0011] A "test strip" or "LFA" can include one or more bibulous or nonbibulous materials. When a test strip includes more than one material, the one or more materials are preferably in fluid communication. One material of the test strip may be overlaid on another material of the test strip, such as filter paper overlaid on nitrocellulose. Additionally or alternatively, a test strip may have a region containing one or more materials (e.g., a medium) followed by a region containing one or more different materials. In this case, these regions are in fluid communication and may or may not overlap each other. Suitable materials for test strips include, but are not limited to, cellulose-derived materials such as filter paper, chromatography paper, nitrocellulose, and cellulose acetate, as well as materials made from glass fiber, nylon, Dacron, polyvinyl chloride (PVC), polyacrylamide, cross-linked dextran, agarose, polyacrylate, ceramic materials, and the like. One or more materials of the test strip may optionally be treated to alter their capillary flow characteristics or the properties of an applied sample. For example, the sample application area of ​​the test strip can be treated with a buffer to correct for the pH or specific gravity of the applied urine sample to ensure optimal testing conditions.

[0012] The one or more materials can be a single structure, such as a sheet cut into strips, or several strips or particulate materials attached to a support or solid surface, such as those found in thin-layer chromatography, and may have an absorbent pad either as an integral part or in liquid contact. The material can also be a sheet with lanes thereon, spotted to induce lane formation, and a separate assay can be performed within each lane. The material can have a rectangular, circular, oval, triangular, or other shape, provided there is at least one transverse direction of the test solution due to capillary migration. Other transverse directions, such as oval or circular pieces that contact the test solution in the center, may occur. However, the primary consideration is that there be at least one flow direction for a given site. In the following discussion, test strips are described by way of example and not limitation.

[0013] If a support is desired or necessary, the support of the test strip is typically water-insoluble and frequently non-porous and rigid, although it may be elastic, usually hydrophobic, and porous, and is typically the same length and width as the strip, although it may be larger or smaller. The support material can be transparent, and can be on the side of the test strip visible to the user, so that when the test device disclosed herein is assembled, the transparent support material forms a protective layer on the test strip that may be exposed to the external environment, such as through an aperture in the front of the test device. A wide variety of non-mobile and non-mobile materials, both natural and synthetic, and combinations thereof, can be used, provided that the support does not interfere with capillary action of one or more materials, non-specifically bind assay components, or interfere with the signal-producing system. Exemplary polymers include polyethylene, polypropylene, poly(4-methylbutene), polystyrene, polymethacrylate, poly(ethylene terephthalate), nylon, poly(vinyl butyrate), glass, ceramics, metals, and the like. The resilient support can be made from polyurethane, neoprene, latex, silicone rubber, etc. Throughout this description, the LFA is described with the understanding that the description of the LFA applies to other types of test strips.

[0014] In some conventional LFAs, test results appear as subtle color changes, increasing user error during reading. For example, an LFA may output a color corresponding to a positive result, but if the color is faint and / or lighting conditions are poor, a user may interpret the test as negative. Furthermore, because some conventional LFAs rely on visual cues to determine results, the test lines corresponding to the result must be sufficiently spaced and / or sufficiently confined to avoid confusion or reading errors. Examples disclosed herein produce improved LFAs that are machine-readable to provide objective, automated result generation through algorithms that reduce and / or otherwise eliminate false positives and / or false negatives due to human error. Furthermore, using an LFA that does not rely on visual cues allows for more test zones to be placed closer together without the risk of misreading the result.

[0015] Because resources may be limited in certain regions of the world, dedicated LFA readers may be too expensive for use in those regions. Therefore, examples disclosed herein provide an improved LFA that can be read using a smartphone application rather than a dedicated reader. While there are several smartphone applications that can read the results of LFA-based tests, such smartphone applications may output inaccurate results due to poor lighting conditions, weak visual indicators on the LFA, and / or poor quality smartphone sensors.

[0016] Examples disclosed herein create an improved LFA to address conventional smartphone application errors and / or human error, which correspond to inaccurate results from conventional LFA readers. Examples disclosed herein provide a signal corresponding to a test result (e.g., one or more analog current and / or voltage values ​​corresponding to the test result, one or more digital current and / or voltage values ​​corresponding to the test result, one or more logic values ​​corresponding to the test result, etc.), providing a more accurate reading than analog systems. Examples disclosed herein correspond to a machine-readable LFA device that does not rely on conventional visual indicators to determine the results of a fluid sample-based test (e.g., an LFA-based test). In examples disclosed herein, the improved LFA provides machine-readable results to a smartphone application. Thus, the results are objective and readable without human interpretation, eliminating operator subjectivity and improving the accuracy of the results. Additionally, there is no need to design and include a reading window on the LFA device. As further disclosed herein, the exemplary LFA device does not need to house a battery (e.g., an energy storage device). For example, LFA devices are battery-less, not wired to a power source, but instead powered by an electromagnetic field generated by a user device such as a reader. Furthermore, accurate results can be easily transmitted to external databases and / or servers, such as remote databases and / or servers located at or otherwise associated with electronic medical records (EMRs), government agencies, non-governmental organizations (NGOs), doctors' offices, hospitals, hospital information systems, laboratory information management software (LIMS) systems, inventory consumption monitors, clinics, and / or other healthcare facilities, medical device manufacturers, healthcare organizations, healthcare information systems, and / or other external entities. In this way, large-scale test results can be generated, collected, and digitally integrated into other healthcare systems, eliminating human transcription errors. Because self-testers do not need to be trained in how to interpret results, the examples disclosed herein also enable self-testing, for example, by non-medical personnel.The self-test may be incorporated into a commercially available device, and the examples disclosed herein may be incorporated into a disposable point-of-care device.

[0017] Examples disclosed herein include an LFA device having a wireless chip that acquires data corresponding to the presence or absence of an analyte in a sample based on an electrical signal generated on the LFA device and transmits the data to a reader. A test result is determined based on a comparison of the electrical signal to one or more thresholds. This comparison can occur on the wireless chip of the LFA and / or in an external reader. In some examples, the wireless chip acquires analog current and / or voltage values ​​from electrodes placed in contact with the porous membrane of the LFA device and transmits the analog current and / or voltage values ​​via an antenna to the reader. In this manner, the reader can compare the analog values ​​to one or more thresholds to determine whether the test result is positive or negative. For example, if the current and / or voltage value(s) exceed the thresholds, the reader determines that the test corresponding to the current and / or voltage value(s) is positive. Similarly, if the current and / or voltage value(s) are below the thresholds, the reader determines that the test corresponding to the current and / or voltage value(s) is negative. In some examples, the wireless chip takes analog current and / or voltage values, converts the analog values ​​to digital values, and transmits the digital values ​​to the reader. In this way, the reader can compare the digital value(s) to one or more thresholds to determine a test result. In some examples, the wireless chip takes analog voltage and / or current values, compares those values ​​(e.g., with or without converting them to digital values) to one or more thresholds, generates a logical value (e.g., high or low) corresponding to a positive or negative test, and transmits those test results to the reader.

[0018] Examples disclosed herein include multiple techniques for generating an electrical signal on an LFA device that indicates the presence or absence of an analyte of interest. For example, to obtain one or more electrical signals corresponding to one or more test results, examples disclosed herein may utilize a bioelectrochemical mechanism (e.g., an energy-generating device) in the test and / or control line of the LFA device. As described further below, the bioelectrochemical mechanism includes a bioelectrochemical cell (e.g., a physical cell or a porous membrane structured to function as a physical cell) that generates an electrical signal in a porous membrane if a target analyte is present. The bioelectrochemical cell may be known as or otherwise include a potentiometric cell, concentration cell, fuel cell, biofuel cell, etc. In some examples, the bioelectrochemical cell generates the electrical signal through one or more bioelectrochemical reactions occurring on the porous membrane. A wireless chip in the LFA device can measure the electrical signal by sensing the current and / or voltage drop between electrodes of the bioelectrochemical cell placed in contact with the porous membrane. In other examples, the LFA device may include a circuit-completion mechanism that generates the electrical signal in the test and / or control line of the LFA device. As described further below, the circuit completion mechanism creates a short circuit in the test zone if the target analyte is present in the sample. For example, the circuit completion mechanism can amplify a substance (e.g., silver) around an immobilized molecule (e.g., gold) in the test zone if the target analyte is present. In this way, the wireless chip can generate a voltage and measure whether current flows from one side of the test zone to the other (e.g., if a short circuit occurs) to identify whether the target analyte is present.

[0019] In some examples of the bioelectrochemical cells disclosed herein, one half of the bioelectrochemical cell is attached to a test zone (e.g., test line, test area, etc.) and / or control zone (control line) of a porous medium (e.g., membrane, paper, and / or other free-compartment or non-compartmental substrate) of an LFA. In some examples, the bioelectrochemical cell is configured to detect glucose and a redox species (e.g., potassium ferricyanide K3 [Fe(CN)6]6). 3- The conjugate pad may be a strip of paper impregnated with a solution of ferrocene or a ferrocene derivative and then dried. Additionally, examples disclosed herein involve labeling (e.g., attaching, binding, etc.) an enzyme (e.g., glucose oxidase (GOx)) to the antibody, analyte, and / or antigen on the conjugate pad. In this manner, when the antibody, analyte, and / or antigen bound to GOx attaches to the target analyte, the immobilized antibody, analyte, and / or antigen corresponding to the target analyte attaches to the test zone, immobilizing GOx. With half of the bioelectrochemical cell attached to the test zone, GOx reacts with the solution in the bioelectrochemical cell to oxidize glucose in the bioelectrochemical cell, as shown in Chemical Reaction Processes 1-3 below. In these processes, (Ox) and (Red) represent the reduced or oxidized state of the enzyme, respectively. Glucose + GOx(Ox) ⇒ Gluconolactone + GOx(Red) (Process 1) GOx(Red) + O2 ⇒ GOx(Ox) + H2O2 (Process 2) Gluconolactone + H2O ⇒ gluconic acid (Process 3)

[0020] Furthermore, the following processes 4-5 show chemical reactions in which the cofactors flavin adenine dinucleotide (FAD) and FADH2 indicate the oxidized or reduced state of the enzyme active center, respectively. GOx(FADH2) + O2 ⇒ GOx(FAD) + H2O2 (Process 4) GOx(FAD) + glucose ⇒ GOx(FADH2) + gluconolactone (Process 5)

[0021] While the examples disclosed herein refer to GOx as the enzyme used to generate a product (e.g., hydrogen peroxide (HO)) corresponding to current flow and / or electron release / movement, the examples disclosed herein may be practiced using additional and / or alternative enzymes. The examples disclosed herein may utilize amino acid oxidase, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, alcohol oxidase, galactose oxidase, and / or any other oxidase as the enzyme used to generate a product (e.g., hydrogen peroxide) that facilitates electron release and / or movement. In some examples, based on the enzyme used, a molecule other than glucose is included to facilitate the reaction that generates hydrogen peroxide.

[0022] In some instances, enzymatic reactions with natural mediators (electron acceptors) (e.g., oxygen) can be used in bioelectrochemical cells. In such instances, glucose is oxidized to gluconolactone and FADH2 is oxidized to FAD, producing products (e.g., HO (hydrogen peroxide)). Additionally or alternatively, glucose can be oxidized in the presence of glucose oxidase, which can reduce oxygen to CH 12 O6 and oxygen (O2) react to form CH 10 O6 and H2O2 (e.g., hydrogen peroxide) can be produced. In some examples, the electrode may be made of a metal (e.g., copper, titanium, brass, silver, platinum, etc.), graphite, or a screen-printed carbon electrode doped with ferrocyanide. In this way, the product (e.g., H2O2) is reduced, and oxidation of the electrode metal or ferrocyanide occurs with the release of electrons. In the latter case, ferrocyanide [Fe(CN)6] 4- reacts to form [Fe(CN)6] 3- The emitted electrons can be measured by a processor (e.g., using current and / or voltage measurements). Normally, copper surfaces are oxidized by air to CuO (Cu(I)). CuO is oxidized by the reduction of HO to CuO (Cu(II)).

[0023] Because a product (e.g., hydrogen peroxide) is generated in the test line and / or control line but is not immobilized there, the product may begin to flow toward the absorbent pad of the LFA device. Accordingly, some examples disclosed herein may include a mechanism to halt (e.g., slow or stop) the flow of fluid and maintain the product, or a portion of the product, at or near the test and / or control line in the test zone until the test is read. A mechanism for halting the flow of fluid may be used in any of the disclosed examples. Some examples disclosed herein slow and halt the flow of fluid by shearing, pinching, and / or cutting (e.g., partially or completely) the porous membrane. Such examples may include a mechanical device that can be user-controlled (e.g., moved, slid, pivoted, twisted, rotated, etc.) to cut the porous membrane. Some examples disclosed herein apply a substance (e.g., a chemical, adhesive, gel, etc.) that is more viscous than the buffer solution to slow and / or stop the flow of fluid. In some examples, after / during application of a mechanism to stop the flow, electrodes may be placed in position to allow the product (e.g., hydrogen peroxide) to react with the electrode(s) after the flow has stopped or slowed down and generate a strong electrical signal (e.g., corresponding to the flow of electrons resulting from the reaction).

[0024] In other examples, alternative reactions can be performed using a bioelectrochemical cell. For example, enzyme-free amperometric redox reactions can be used in a bioelectrochemical cell. For example, the amperometric signal of an LFA can be measured without the GOx enzyme because the gold in the AuNPs can function as a catalyst (e.g., if the GOx in the conjugate is reseeded with AuNPs). In these examples, thiosulfate can be used to improve the signal, as shown below in Processes 6-8. In Process 11 below, thiosulfate, ferricyanide, and KBr or KCl react, and the AuNPs catalyze the reduction to ferricyanide, generating an electronic signal. The KBr or KCl can be included in the buffer solution and / or dried within a portion of the porous membrane and resuspended in the buffer solution. (Oxide)2S2O3 2- ⇒S4O6 2- +2e - (Process 6) (reduced) [Fe(CN)6] 3- +e - ⇒[Fe(CN)6] 4- (Process 7) 2[Fe(CN)6] 3- +2S2O3 2- ⇒2[Fe(CN)6] 4- +S4O6 2- (Process 8)

[0025] Alternatively, Processes 9-11 below show alternative chemical reactions for GOx-glucose oxidation. As shown in the previous process, oxygen can reactivate or reoxidize GOx to its active form. While Processes 9-11 are described in combination with ferricyanide, Processes 9-11 can be used with other substances in their oxidized form (e.g., quinones, ferrocene, osmium complexes, etc.). The quinones, ferrocene, osmium complexes, etc. may be contained in a buffer solution and / or dried within a portion of the porous membrane and resuspended in a buffer solution. Glucose + GOx(Ox) ⇒ Gluconolactone + GOx(Red) (Process 9) GOx(Red)+2[Fe(CN)] 3- ⇒GOx(Ox)+2[Fe(CN)] 4- (Process 10) Gluconolactone + H2O ⇒ gluconic acid (Process 11)

[0026] Processes 4 and 11 result in a decrease in the pH level of the solution (e.g., to the acidic regime in the case of a low buffer system) that corresponds to an electromotive force on an electrode placed next to the test line of the LFA where no GOx reaction occurs. When a change in pH level occurs in a low concentration buffer, a measurable Nernst voltage and / or current is generated.

[0027] In the redox cycle of GOx, electrons are transferred to one half of the bioelectrochemical cell, [Fe(CN)6] 3- is reduced to [Fe(CN)6] 4- The ferricyanide molecules act as an electron mediator and can eventually diffuse to the electrode. The concentration difference between the electrode at the top of the cell and the electrode at the bottom of the cell allows the Nernst equation to be satisfied:

number

number

[0028] In some examples disclosed herein, the medium (e.g., membrane, paper, and / or substrate) of a lateral flow immunoassay device can function as a bioelectrochemical cell. For example, instead of using dry paper, glucose and redox species function as the bioelectrochemical cell. An assay buffer containing glucose and redox species can be applied to the lateral flow immunoassay device. In some examples, the buffer can contain glucose and redox species to dilute the sample and promote a reaction that results in a current or voltage. In these examples, the membrane of the lateral flow immunoassay device functions as a salt bridge. In this manner, when an immobilized antibody, analyte, and / or antigen corresponding to a target analyte attaches to the test zone to immobilize GOx, the GOx reacts with the glucose and redox species in the assay buffer, diffusing electrons to the media zone outside the test zone, generating a voltage and / or current. Thus, the bioelectrochemical cell is based on a target zone and a zone outside the target zone. Thus, a first electrode can be placed in the test zone, a second electrode can be placed in a zone outside the test zone, and a voltage and / or current can be measured between the two test zones to determine whether a target analyte is present. As used herein, a bioelectrochemical cell is a cell that converts chemical energy from a fuel and an agent (e.g., an oxidant) into electricity through a pair of oxidation-reduction reactions. A bioelectrochemical cell can be a biofuel cell (e.g., a fuel cell that uses an enzyme as a catalyst to oxidize its fuel), a concentration cell (e.g., an electrolytic cell that includes two half-cells with identical electrodes and generates a voltage and / or current when the concentrations of the two half-cells are different (e.g., there is a GOx glucose reaction at one electrode and no reaction at the other electrode)), a galvanic cell (e.g., including two different metals immersed in an electrolyte solution connected by a salt bridge or porous medium), and / or any other cell that converts chemical energy into electricity.

[0029] As disclosed above, in some examples, the LFA device can generate or measure an electrical signal corresponding to a test result using a circuit-completion mechanism in the test and / or control lines of the LFA device. For example, a machine-readable LFA device has a test zone that functions like an electrical switch. In these examples, the conjugate pad contains gold nanoparticles labeled with antibodies, analytes, and / or antigens corresponding to the target analyte. In this manner, if the sample contains the target analyte, the target analyte will attach to the gold-labeled antibody, analyte, and / or antigen and be immobilized in the test zone by the corresponding immobilized antigen, analyte, and / or antibody. An autocatalytic silver enhancer (e.g., silver ions and a reducing agent such as hydroquinone, aminophenol, or ascorbic acid) is applied to the test zone, causing the silver to react with the gold and amplify in size. When the silver exceeds a certain size and amplifies, the amplified silver attached to each gold nanoparticle on the test zone comes into contact with each other, creating a connection, increasing conductivity, decreasing resistance, and / or creating a short circuit between the electrodes. Examples disclosed herein apply electrical connections to each side of the test zone, and a voltage can be applied to one side of the electrical connections. If the target analyte is present, silver amplifies, creating a connection resulting in high conductivity, low resistance, and / or a short circuit, and when a voltage is applied, current flows from one electrical connection to the other. Thus, examples disclosed herein determine the presence of the target analyte in a sample (e.g., corresponding to a positive test result) by measuring a signal (e.g., current flow and / or resistance between the electrical connections to the test line (e.g., a short circuit has low resistance and an open circuit has high (infinite) resistance)). If the measured signal has a current above a current threshold or a corresponding resistance below a resistance threshold, examples disclosed herein flag the test as positive for the corresponding target analyte; if the measured signal has a current below a current threshold or a corresponding resistance above a resistance threshold, examples disclosed herein flag the test as negative for the corresponding target analyte, eliminating the need for a visual indicator.

[0030] Alternatively, the silver amplification reaction (reduction of silver by oxidation of a reducing agent, resulting in electron e - and proton H + is released and recombines with H2O to form H3O + (becomes H3O) + The production of ions changes the pH of the poorly buffered reaction solution. One type of bioelectrochemical cell in which silver amplification occurs in the upper part of the cell is:

number

[0031] Because an LFA device may accommodate one or more specific durations during which a user must perform a particular action (e.g., a duration for applying sample and / or buffer, a duration for obtaining results after applying sample, a duration for scanning the LFA device with a reader, a duration for moving mechanical parts of the LFA device, etc.), examples disclosed herein include mechanisms and processes for tracking time and / or guiding a user to perform one or more steps. For example, after sample and / or buffer are applied to the LFA, a user may need to wait a first duration before obtaining results. Examples disclosed herein may include a timer in the LFA device and / or reader to track the duration(s) and guide the user through the testing process. In some examples, the timer is powered by the current and / or voltage generated by the bioelectrochemical cell. In some examples, the LFA device may transmit timing information to the LFA reader, and the LFA reader may display and / or otherwise indicate the one or more durations to the user. In some examples, the LFA reader may track duration based on confirmation from the user and may guide the user on when to perform certain tasks to ensure that the tasks are not performed too early or too late (e.g., not reading the results too early or too late, not scanning the LFA too early or too late, not adjusting the LFA device too early or too late, etc.). By providing a reader to guide the user through the test production, the LFA device may be operated by users with less training and / or may be performed by less educated users. Additionally, patients can perform self-tests on the reader by following guides presented on the reader.

[0032] 1A illustrates an exemplary environment 100 that includes an exemplary machine-readable LFA generator 102 that generates an exemplary machine-readable LFA chip, strip, or LFA device 104 (shown in an overhead view). The exemplary machine-readable LFA device 104 includes an exemplary sample pad 106, an exemplary conjugate release pad 108, an exemplary porous medium 109, an exemplary test area 110, exemplary bioelectrochemical cells 111a-n, an exemplary absorbent pad 112, an exemplary inlet 113, an exemplary wireless chip 114, and an exemplary antenna 115. The environment 100 of FIG. 1A further includes an exemplary user device or reader 116 for determining test results (e.g., diagnostic test results) of a sample that has been applied to the exemplary machine-readable LFA device 104. The exemplary reader 116 includes an exemplary machine-readable LFA reader application 117, an exemplary antenna 118, and an exemplary user interface 120. Although the example of FIG. 1A determines a test result based on bioelectrochemical cells 111a-n, FIG. 1A may be described in conjunction with other techniques for determining a test result based on an electrical signal, as disclosed further herein.

[0033] 1A generates an exemplary machine-readable LFA device 104 (and / or an exemplary machine-readable LFA device 300 of FIG. 3A). For example, the machine-readable LFA generator 102 generates the machine-readable LFA device 104, which includes an exemplary sample pad 106, an exemplary conjugate release pad 108, an exemplary porous medium 109, an exemplary test area 110, exemplary bioelectrochemical cells 111a-n, an exemplary absorbent pad 112, an exemplary inlet 113, an exemplary wireless chip 114, an exemplary antenna 115, and / or wires or etchings (not shown) included in the housing structure. The number of tests, the type of tests (e.g., pregnancy, Ebola, HIV, influenza, COVID, cancer, sexually transmitted disease (STD), etc.), the number of control zones, the type of control zones (e.g., positive control, negative control, etc.), and / or the type of machine-readable LFA are based on instructions from a user and / or manufacturer. For example, if a user desires to include a single test for pregnancy in the exemplary machine-readable LFA device 104, the machine-readable LFA generator 102 generates exemplary conjugate regions that include antibodies, analytes, and / or antigens corresponding to target analytes corresponding to pregnancy, where the antibodies, analytes, and / or antigens are labeled with specific molecules (e.g., gold nanoparticles, GOx, etc.). In such an example, the machine-readable LFA generator 102 generates a test area 110 including immobilized antibodies, analytes, and / or antigens that bind to or otherwise attach to a target analyte and a bioelectrochemical cell (e.g., an enzyme substrate (e.g., glucose) and / or a reducing agent (e.g., paper impregnated with hydroquinone, aminophenol, vitamin C (e.g., ascorbic acid found in vitamin C), etc.), and / or an electron mediator or redox species (e.g., potassium ferricyanide, ferrocene, oxygen, ferrocene derivatives, etc.) that includes a moiety attached to the test area 110. Additionally, the exemplary machine-readable LFA generator 102 generates or otherwise attaches a wireless chip 114 to attach to the bioelectrochemical cell to determine whether the sample (e.g., a biological sample) is positive or negative for the target analyte corresponding to pregnancy.An exemplary machine-readable LFA generator 102 is further disclosed in connection with FIG.

[0034] The exemplary machine-readable LFA device 104 of FIG. 1A is a bioelectrochemical cell-based LFA (e.g., a concentration cell with Nernst voltage sensing) including exemplary bioelectrochemical cells 111a-n. However, the machine-readable LFA device 104 may be an alternative device capable of obtaining data related to test results on the LFA 104. For example, as further disclosed below in connection with FIG. 3A, the exemplary machine-readable LFA device 104 may instead be a circuit-completion-based LFA device (e.g., an electrical short via a low-resistance test line). In some examples, the exemplary machine-readable LFA device 104 is a non-visible indication biosensor device. For example, the LFA device 104 may not output a visible indication to a user (e.g., because there are no gold nanoparticles on the device) and / or the visible indication is not visible to a user (e.g., because the housing covers a porous medium in which the visible indication may be implemented). In some examples, the LFA device 104 is a non-visible indication circuit-completion device. In some examples, the LFA device 104 is a visual indication circuit-complete device and / or a biosensor device that can provide a visual indication of a result and transmit the result wirelessly to a reader. The LFA device 104 may also be a point-of-care device and / or a rapid diagnostic device that includes an application specific integrated circuit (e.g., the exemplary wireless chip 114).

[0035] The exemplary machine-readable LFA device 104 of FIG. 1A is a device that includes a sample pad 106 (e.g., sample pad, sample region, sample area, sample zone, etc.). For example, the LFA device 104 may be a porous membrane device, a porous medium device, a fluid transport medium device, a test strip device, a lateral flow test strip device, and / or any fluid sample device. The sample pad 106 is structured to function as a sponge that retains a fluid sample applied to the sample pad 106. In some examples, the sample pad 106 includes buffer components (e.g., salts, surfactants, etc.) to ensure that target analytes that may be present in the sample can bind to components of the conjugate release pad 108. When the sample pad 106 is submerged, fluid retained in the sample pad 106 flows to the conjugate release pad 108. The conjugate pad 108 includes a label or conjugate configured to bind the target analyte. For example, the conjugate release pad 108 includes conjugates or probes (e.g., antibodies specific for one or more target analytes) labeled with a detectable label, tag, linker, antibody, analyte, antigen, GOx, gold nanoparticles, etc. Target analytes are components corresponding to a particular condition or disease. Thus, the presence of target analytes in a sample corresponds to the presence of a corresponding condition and / or disease in the patient providing the sample. If the sample contains one or more of the target analytes, the conjugates and / or probes labeled with GOx, gold nanoparticles, etc., attach to the corresponding target analytes. The sample (e.g., including the probes if the corresponding target analytes are present in the sample) continues to flow through the exemplary porous medium 109 of the machine-readable LFA device 104 toward the absorbent pad 112.

[0036] The sample flows across the medium 109 in FIG. 1A, and the sample flows across the test area 110. The medium 109 may be a porous membrane, a nitrocellulose membrane, paper, or other substrate, including a free-compartment substrate that propagates the flow of a biological sample and / or buffer. The test area 110 includes test zones (e.g., test lines, test areas, test regions, etc.) and / or control zones (e.g., control lines, control areas, control regions, etc.). The test zones contain specifically immobilized antibodies, analytes, or antigens that react with corresponding target analytes attached to probes and / or conjugates. Thus, if the target analyte corresponding to a particular test zone is present in the sample, the GOx and / or gold nanoparticles will be immobilized in the particular test zone. In some examples, the test zones of the LFA 104 are known as multiplexed and correspond to various conditions or diseases. Multiplexing involves constructing multiple test zones or test lines to detect multiple marks (e.g., multiple types of antibodies / antigens / analytes) in a single sample. Multiplexing has application, for example, in a single diagnostic test that can test for multiple types of sexually transmitted diseases. In some examples, the test area 110 includes a control zone that immobilizes specific and / or excess conjugates that flow through the control zone. The control zone corresponds to the target that has dried down to the porous medium 109, indicating that the test is ready to be read (e.g., when the test is complete).

[0037] The test area 110 of FIG. 1A further includes exemplary bioelectrochemical cells 111a-n (e.g., concentration cells). FIG. 1A shows portions of the bioelectrochemical cells 111a-n. Other portions are shown in FIGS. 1B-2E and / or 2I-2K. In some examples, the potentiometry cells 111a-n are paper strips or other substrates impregnated with an enzyme substrate (e.g., glucose) and / or a reducing agent (e.g., hydroquinone, aminophenol, ascorbic acid found in vitamin C, etc.), and / or an electron mediator or redox species (e.g., potassium ferricyanide, ferrocene, oxygen, ferrocene derivatives, etc.). However, the bioelectrochemical cells 111a-n can be any type of bioelectrochemical cell, as described above in connection with Processes 1-11 above. When GOx (which oxidizes glucose) or gold nanoparticles (which autocatalytically reduce silver nitrate (e.g., vitamin C and / or another reducing agent)) are attached to the test and / or control zones, the corresponding bioelectrochemical cells 111 a-n are activated by the generation of a voltage according to the Nernst equation, which can be read out via the wireless chip 114. Thus, the wireless chip 114 performs bioelectrochemical measurements using the exemplary bioelectrochemical cells 111 a-n, and the wireless chip 114 passively measures the potential between two different portions of the biofuel cell 111 a-n using two electrodes. In some examples, the bioelectrochemical cells 111 a-n are fluidly coupled to (e.g., attached to) the test and / or control zones during fabrication. In some examples, the bioelectrochemical cells 111a-n are separated from the test and / or control zones during manufacturing, and the exemplary LFA device 104 includes a mechanical device that automatically and / or manually pushes the bioelectrochemical cells into contact (e.g., fluid contact) with the test and / or control zones when a test is to be performed (e.g., automatically when a sample is applied to the LFA 104 and / or manually via user intervention, pushing the bioelectrochemical cells into contact with the zones).

[0038] The test area 110 of FIG. 1A further includes an exemplary absorbent pad 112. The exemplary absorbent pad 112 of FIG. 1A is an absorbent material that absorbs liquid through the LFA. In some examples, the absorbent pad 112 includes a cellulose filter. The absorbent pad 112 prevents backflow of liquid. In some examples, the absorbent pad 112 also functions as a waste container.

[0039] 1A is structured to allow water or another buffer applied to the sample pad 106 to flow into the absorbent pad 112. In some examples, the water and / or buffer is enclosed in a holding device (e.g., a frangible enclosure such as a bag), and when the user presses and / or moves a component of the LFA device 104, the holding device releases the buffer (e.g., by breaking the bag). In some examples, the sample pad 106 may be more than one sample pad (e.g., one for the sample and another for water / buffer and / or additional reagents). As water and / or buffer solution flows through the bioelectrochemical cells 111a-n, a current will flow if the test and / or control zones are attached to GOx and / or gold nanoparticles (e.g., based on mixing the conjugate with the enzyme substrate, reducing agent, and / or electron mediator of the bioelectrochemical cells 111a-n) by resuspending the water and / or buffer solution with dried reagents. The central area (e.g., the constricted area in FIG. 2A) between the first portion (e.g., the top portion in FIG. 2A) and the second portion (e.g., the bottom portion in FIG. 2A) of the bioelectrochemical cells 111a-n acts as a salt bridge for diffusion-induced homogenization of the concentration gradient, such that electrons lost in the first portion of the bioelectrochemical cells 111a-n (e.g., due to reactions occurring when a target analyte and corresponding conjugate are suspended in a test zone or control zone) flow toward the second portion of the bioelectrochemical cells 111a-n, corresponding to a measurable voltage drop and / or current from the first portion of the bioelectrochemical cells 111a-n to the second portion of the bioelectrochemical cells 111a-n. Additionally or alternatively, the paper / membrane type can reduce diffusion.

[0040] The exemplary machine-readable LFA device 104 further includes an exemplary wireless chip 114. The wireless chip 114 is a near-field communication (NFC) chip. Thus, the wireless chip 114 can be powered by and / or communicate with the reader 116 via an NFC communication protocol. Alternatively, the exemplary wireless chip 114 may be a radio frequency identification (RFID) chip or any other type of wireless chip. The wireless chip 114 includes pins coupled to connectors (e.g., wires, etchings, etc.) that couple to electrodes (e.g., directly or via a front-end device, as described further below). The electrodes connect to two ends of each bioelectrochemical cell 111 a-n and / or on different sections of the porous membrane 109. In this way, when a voltage and / or current is generated by the bioelectrochemical cells 111 a-n, the voltage drop and / or current between the two electrodes (e.g., connected to opposite portions of the bioelectrochemical cells or located in different positions on the porous membrane 109) is higher than a threshold. In some examples, the generated voltage and / or current can be used to power the wireless chip 114 (e.g., to power the wireless chip 114 for storing test results). The exemplary wireless chip 114 includes hardware, software, and / or firmware that can measure current, electromotive force, or voltage drop and / or current to determine whether a target analyte is present in a sample. The wireless chip 114 may include an ASIC for encoding manufacturing and / or identification information. The exemplary wireless chip 114 is powered by the exemplary antenna 115. When the exemplary reader 116 generates a magnetic field within a threshold distance to the exemplary antenna 115, a current is generated in the antenna 115 and the corresponding energy is used to power the wireless chip 114.Once powered, the wireless chip 114 can transmit identification information (e.g., a device identifier, a test identifier, a serial number, a product code, etc.) to the exemplary reader 116 and / or may transmit measurements corresponding to test results (e.g., analog and / or digital values ​​corresponding to voltage and / or current measurements obtained at the LFA device 104). In some examples, communications between the wireless chip 114 and the reader 116 are encrypted using encryption techniques known by both the wireless chip 114 and the reader 116. In some examples, the wireless chip 114 may flag each test zone and / or control zone as positive or negative based on the measured current, electromotive force, and / or voltage drop, store the results corresponding to the flag(s), and / or transmit the results using the antenna 115. Additionally, the exemplary wireless chip 114 may transmit identification information corresponding to the LFA identifier, test and / or control zone identifiers, etc. along with the results. In some examples, the wireless chip 114 is coupled to a circuit-complete-based LFA. While the example of FIG. 1A includes the exemplary wireless chip 114 as part of the exemplary LFA 104, the wireless chip may be integrated into an external device. In such examples, the LFA 104 may include components (e.g., an interface) that allow electrodes of the LFA 104 to connect to the wireless chip 114. In this manner, the design of the LFA 104 can be simplified to reduce the size and / or cost of the LFA 104, and multiple LFAs can be connected to the wireless device 114 to transmit test results to the exemplary reader 116. The operation of the wireless chip 114 in association with a circuit-complete-based LFA is further disclosed below in connection with FIG. 3A. The exemplary wireless chip 114 is further disclosed below in connection with FIG. 5.

[0041] 1A is a smartphone that includes a machine-readable LFA reader application 117, an exemplary antenna 118, and an exemplary user interface 120. Alternatively, the exemplary reader 116 may be a tablet, a personal digital assistant, a laptop, a standalone LFA reader device, and / or any other processing device that includes or otherwise communicates with the exemplary machine-readable LFA reader application 117, the exemplary antenna 118, and / or the exemplary user interface 120. The exemplary machine-readable LFA reader application 117 is an application that can be installed, downloaded, and / or coded within the exemplary reader 116. In some examples, the exemplary machine-readable LFA reader application 117 can be provided via a near field communication tag or a Bluetooth device.

[0042] In some examples, the reader 116 can be split into multiple readers. In these examples, a first reader 116 obtains information from the LFA 104 and guides a user through a process using the LFA 104, while a second reader 116 obtains test results from the LFA 104. For example, in a hospital, hospital information system, LIMS system, inventory consumption monitor, clinic, test site, etc., a first reader can guide a first user to obtain a sample using the first LFA reader, and once the sample is obtained, the first reader can communicate with a second reader to send LFA device information and start a timer on the second reader for when the test will be ready. In this manner, a first user can provide an LFA device to a second user, who can scan the LFA device when they are ready to use the second reader.

[0043] 1A directs components of reader 116 to generate electromagnetic signals at various times: (a) to acquire identification information from LFA device 104 at a first time, (b) to acquire identification information from LFA device 104 at a second time before acquiring results to verify that the correct device is being read, and (c) to acquire results (e.g., one or more digital voltages and / or currents corresponding to the results) from LFA device 104. The example LFA reader application 117 generates an electromagnetic field at the second time to verify identification information and ensure that the user is reading the test from the correct LFA device (e.g., when reading multiple tests simultaneously). The example machine-readable LFA reader application 117 identifies the results of the LFA-based tests by interacting with wireless chip 114 (e.g., receiving radio signals that identify the test results). For example, the machine-readable LFA reader application 117 controls components of the reader 116 to obtain identification information and / or test results corresponding to the machine-readable LFA device 104 via NFC, RFID, etc. signals transmitted from the wireless chip 114. In some examples, the LFA reader application 117 determines information based on the obtained identification information. For example, the LFA reader application 117 can determine whether a test has already been read, the type of test being performed, algorithms for identifying and / or categorizing the results of the test, whether a test has expired or whether a test has been recalled, etc. The algorithms (e.g., corresponding to how and when to read one or more electrical signals from a particular LFA device) may be stored locally on the reader 116 and / or may be configured, reconfigured, updated, etc. remotely (e.g., via a patch, update, remote instruction, etc.).Once test results (e.g., samples from LFA device 104) are obtained, machine-readable LFA reader application 117 determines whether the test is ready (e.g., based on a flag corresponding to the control zone), and if so, determines the results of the test based on a corresponding algorithm (e.g., using voltage and / or current samples from the test line), displays the results using exemplary user interface 120, stores the results in a local database, and / or transmits the results to a monitoring entity for monitoring and / or statistical analysis. In this manner, a manufacturer or other party can process the results, perform diagnostics, and / or identify whether a particular LFA device is likely counterfeit (e.g., if the number of results corresponding to the same identification information is determined to be above a threshold). In some examples, LFA reader application 117 transmits the raw data. In some examples, LFA reader application 117 obtains (e.g., from wireless chip 114) and / or determines (e.g., based on the identification information from wireless chip 114) various other contextual information, including lot number, use-by date, expiration date, test information, signal quality information, chain of custody, etc. Additionally or alternatively, in some examples, the LFA reader application 117 transmits processed data or data obtained from one or more levels of analysis. An exemplary machine-readable LFA reader application 117 is further disclosed below in connection with FIG.

[0044] 1A wirelessly powers and / or communicates with (e.g., via example antenna 115) example wireless chip 114. For example, based on instructions from example machine-readable LFA reader application 117, antenna 118 generates a magnetic field to power example wireless chip 114 and receives wireless information (e.g., identifiers, test results, etc.) from example wireless chip 114.

[0045] Figure 1B is a side view of the LFA components of the LFA device 104 of Figure 1A. Figure 1B includes an exemplary sample pad 106 of Figure 1A, an exemplary conjugate pad 108, an exemplary porous medium 109, a part (s) of exemplary bioelectrochemical cells 111a - 111n, and an exemplary waste liquid pad 112. The exemplary bioelectrochemical cells 111a - n are connected to the exemplary wireless chip 114 of Figure 1A via electrodes as described above in connection with Figure 1A.

[0046] Figure 2A shows an exemplary implementation of a portion of the machine - readable LFA device 104 of Figure 1A when implementing the exemplary bioelectrochemical cells 111a - n of Figure 1A to generate an electrical signal corresponding to a test analysis by an enzymatic reaction. The example of Figure 2A includes an exemplary porous medium 109 of Figure 1A, exemplary bioelectrochemical cells 111a - d (e.g., corresponding to the bioelectrochemical cells 111a - n of Figure 1A), an exemplary inlet 113, an exemplary wireless chip 114, and an exemplary antenna 115. The exemplary porous medium 109 has two control lines, two test lines, and four bioelectrochemical cells 111a - d, but the porous medium 109 can have any number of test lines, control lines, and / or bioelectrochemical cells. Additionally, or alternatively, as further described below, other techniques (e.g., circuit - completion techniques that utilize the porous membrane 109 as a bioelectrochemical cell) can be used to acquire an electrical signal corresponding to the test result.

[0047] The exemplary porous medium 109 of Figure 2A is structured with two test lines (e.g., T1 and T2) and two control lines (e.g., positive control (PC) and negative control (NC)). The negative control line includes an immobilized antibody and / or antigen that binds to the corresponding target analyte that binds to the immobilized antibody when the sample is applied to the sample pad 106. The negative control line is included to verify that the current generated by the attached bioelectrochemical cell 111d is strong enough for a valid test measurement. For the test to be valid, the amount of voltage and / or current across the bioelectrochemical cell 111d via the negative control line needs to be below a threshold value.

[0048] The positive control line contains immobilized antibodies, analytes, and / or antigens that specifically bind, and / or excess GOx- and / or gold nanoparticle-labeled conjugates and / or GOx- and / or gold nanoparticle-labeled probes that flow from the conjugate pad 108 toward the absorbent pad 112. When the sample flows toward the absorbent pad 112, the positive control line is the last section to attach to the conjugates and / or probes, causing the bioelectrochemical cell 111a to generate a voltage and / or current. In this manner, the reader 116 indicates readiness for testing when the voltage and / or current measurement of the bioelectrochemical cell 111a is positive (e.g., exceeds a threshold amount of voltage and / or current). Exemplary test lines T1 and T2 each contain immobilized antibodies, analytes, and / or antigens corresponding to different target analytes. Thus, if the target analyte of T1 is present in the sample, the target analyte (attached to the conjugated antibody, analyte, and / or antigen labeled with GOx and / or silver nitrate) will be immobilized at the T1 line.

[0049] The exemplary bioelectrochemical cells 111a-d in FIG. 2A are strips of paper impregnated with redox species (e.g., (i) potassium ferricyanide and (ii) (a) glucose or (b) ascorbic acid) and dried. In some examples, the bioelectrochemical cells 111a-d are not initially attached to the porous medium 109, and the housing includes a mechanical device that automatically and / or manually pushes the bioelectrochemical cells into contact with the porous medium 109 for testing. In other examples, the bioelectrochemical cells 111a-d are initially attached to the porous medium 109. The bottom halves of the bioelectrochemical cells 111a-d are coupled to the wireless chip 114 via a single pin, although the bottom halves of the bioelectrochemical cells 111a-d may be coupled to the wireless chip 114 via four separate pins.

[0050] The exemplary inlet 113 in FIG. 2A allows water or buffer to resuspend the dried reagents in the bioelectrochemical cells for testing. Thus, before, during, and / or after sample is added to the sample pad 106, a user applies water and / or buffer to the sample pad 106 and / or a separate sample pad, and the water and / or buffer flows through the inlet, resuspending the dried reagents in the bioelectrochemical cells 111a-d. In this manner, the central section of the bioelectrochemical cells 111a-d functions as a salt bridge for diffusion-induced homogenization of the concentration gradient. This allows GOx (if immobilized on the test or control line) to oxidize glucose in the corresponding bioelectrochemical cell 111a-d. Alternatively, this allows silver nitrate to oxidize ascorbic acid in the corresponding bioelectrochemical cell 111a-d, resulting in H + (H3O + ), which may allow a reducing agent (e.g., ascorbic acid) to reduce silver nitrate. When one or more half of the bioelectrochemical cells 111a-d oxidizes in the redox cycle of GOx, electrons are transferred, producing [Fe(CN)6] in one half of the bioelectrochemical cell. 3- is reduced to [Fe(CN)6] 4- The ferricyanide molecules act as an electron mediator and can eventually diffuse to the electrode. The concentration difference between the upper and lower cells allows the Nernst equation to be satisfied:

number

[0051] 2A is structured around other components of the exemplary machine-readable LFA device 104. Connections between the bioelectrochemical cells 111a-d and / or the wireless chip 114, the antenna 115 can be via wires or etchings.

[0052] 2B illustrates an alternative implementation of the example antenna 115 of FIG. 2A within the LFA device 104 of FIG. 1A. In the example of FIG. 2B, the antenna is structured in a dedicated space (rather than around components of the machine-readable LFA device 104). Additionally or alternatively, the example antenna 115 may be structured in a different configuration.

[0053] FIG. 2C illustrates exemplary implementations 200a-200f of one or more of the bioelectrochemical cells 111a-n of FIGS. 1A, 1B, 2A, and / or 2B within the LFA device 104 of FIG. 1A. While FIG. 2C illustrates six different implementations 200a-200f, there may be other implementations of the bioelectrochemical cells 111a-n. One or more of the bioelectrochemical cells 111a-n may be implemented as a combination of one or more morphological variations of the exemplary implementations 200a-200f. For example, implementation 200f may include any number of serpentines between the first and second portions of implementation 200f. Alternatively, the porous membrane 109 may function as a bioelectrochemical cell, as further described below in connection with FIG. 2D.

[0054] FIG. 2D shows a top view of an alternative exemplary implementation of the porous medium 109 of the machine-readable lateral flow immunoassay 104 of FIG. 1A for generating an electrical signal corresponding to a test analysis via an enzymatic reaction. As shown in FIG. 2D, the porous medium 109 includes a positive control zone (PC), a test zone (T1), and a negative control zone (NC). Additionally or alternatively, the porous medium 109 may include any number and / or types of control and / or test zones. The exemplary porous medium 109 of FIG. 2D includes an exemplary membrane compression or cut 201, exemplary electrodes 202a-202f corresponding to the different zones. While the exemplary electrodes 202a-f in FIG. 2D have different widths, the exemplary electrodes 202a-f may be the same width and / or structured to have any width. The width of electrodes 202a-f can be based on the geometry of porous membrane 109, the size of the salt bridge between the working electrode (e.g., electrode 202a) and the reference electrode (e.g., electrode 202b), the overlap between specific test zones and non-reference areas, etc. In some examples, electrodes 202a, 202c, and 202e are wider than electrodes 102b, 102d, and 102f (e.g., reference electrodes), and electrodes 202a, 202c, and 202e are wider than the test bands to allow for the most flexible positioning tolerances during assembly of the test bands and their manufacturing / printing. The spacing between the working and counter electrode pairs [electrode 202a, reference electrode 202b], [electrode 202c, reference electrode 202d], and [electrode 202e, reference electrode 202f] is as small as possible (e.g., 10 nanometers (nm) to 5 millimeters (mm), but may be as small as 1 nm). Exemplary electrodes 202a-202f may be silver carbon electrodes, copper electrodes, graphitic carbon electrodes, titanium electrodes, brass electrodes, platinum and palladium electrodes, screen-printed carbon electrodes doped with ferrocyanide or any other oxidizable material or electron donor, and / or any other type of electrode. In some examples, electrodes 202a, 202c, 202e are copper electrodes and the reference electrode is a carbon electrode.By having a pair of electrodes (e.g., a working electrode and a reference electrode) relative to a single test and / or control line, a salt bridge can be created across the porous membrane 104 with low impedance between the pair of electrodes. In this manner, the voltage and / or current between the pair of electrodes can be read without using an external power source to facilitate generation of the voltage and / or current. In some examples, the electrodes 202a-202f do not engage with the porous medium 109 until it is time to read the results. Therefore, one or more mechanical devices can be used to keep the electrodes 202a-202f disengaged from (e.g., not in contact with) the porous medium 109 until it is time to read the results. An example of one or more mechanical devices for engaging and / or disengaging the electrodes 202a-202f from the porous medium 109 is further disclosed below in connection with FIGS. 2N-2R.

[0055] In the example of Figure 2D, the porous medium 109 itself serves as a salt bridge for the biofuel cell. The biofuel cell uses an additional enzyme (e.g., a reductase such as laccase) at the counter electrode (e.g., the cathode). In such an example, the laccase reduces oxygen (O2) from the reaction at the anode to 4e - +4H +The bioelectrochemical cells (e.g., biofuel cells) 111a-d of Figures 2A and / or 2B are impregnated with glucose and redox species (e.g., after buffer resuspends the desiccant of the biofuel cells 111a-d) to generate a voltage and / or current when the target analyte reacts with the glucose in the biofuel cell, with the redox species acting as an electron mediator. In the example of Figure 2D, no chromatography paper (e.g., the impregnated paper of the biofuel cells 111a-d described above) is included, and the glucose and redox agent are contained in the assay buffer. In this way, when the assay buffer containing glucose and redox agent is applied to the sample pad 106, the assay buffer saturates the porous medium 109. In this way, if the target analyte is present in the sample, the corresponding conjugate / probe labeled with GOx / gold nanoparticles becomes immobilized in the corresponding test zone. After the assay buffer is applied, the porous medium 109 is saturated with glucose and redox agent, so that GOx reacts with glucose on the test zone (e.g., oxidizes it), and the redox agent acts as an electron mediator, forming [Fe(CN)6] in the corresponding test zone. 3- is reduced to [Fe(CN)6] 4- This result corresponds to a measurable voltage drop and / or current between the test and non-test zones of the porous medium 109, which can be measured by the exemplary wireless chip 114 via the exemplary electrodes 202a-f. Thus, the example of FIG. 2D is a bioelectrochemical cell integrated into an LFA.

[0056] As noted above, in some instances, the enzymatic reaction can occur with a natural mediator (e.g., oxygen) in the bioelectrochemical cells 111a-d. In such instances, glucose can be oxidized to gluconolactone and FADH2 can be oxidized to FAD, thereby producing HO. Additionally, or alternatively, glucose can be oxidized in the presence of glucose oxidase, which can reduce oxygen, to produce CH. 12 O6 and oxygen (O2) react to form CH 10O6 and products (e.g., H2O2 (hydrogen peroxide)) can be produced. In such instances, the electrode may be made of a metal (e.g., copper) or may be a screen-printed carbon electrode doped with ferrocyanide. In this way, H2O2 is reduced and oxidation of the electrode metal or ferrocyanide occurs with the release of electrons. In the latter case, ferrocyanide [Fe(CN)6] 4- reacts to form [Fe(CN)6] 3- The emitted electrons can be measured by a sensor (e.g., using current and / or voltage measurements) and processed by a processor (e.g., locally in the wireless chip 114 and / or in the reader 116) to determine a test result. Typically, a copper surface is oxidized by air to become CuO (Cu(I)). CuO is oxidized by the reduction of HO to become CuO (Cu(II)).

[0057] As described above, intermediate reaction products (e.g., hydrogen peroxide) are generated by the enzyme glucose oxidase on the control and / or test lines in the porous membrane 109 of FIG. 2D. In some instances, glucose from the buffer solution may react with glucose oxidase on the LFA (e.g., outside the control or test lines) to generate small amounts of product (e.g., hydrogen peroxide) on the test line where glucose oxidase is not recruited (e.g., when the target analyte is not present in the sample). However, the concentration of product in these areas is too low to generate enough electrons at the electrode on the target line if the target analyte is not present in the sample. Therefore, in these instances, small amounts of product do not generate a false-positive test result. After the product (e.g., hydrogen peroxide) is generated, it is diluted with the surrounding acetate buffer. Therefore, without stopping the flow, the product may migrate toward the absorbent pad 112 and not be able to react at all or sufficiently with the electrodes 202a-202f, resulting in no or reduced current signal. Furthermore, without stopping the flow, the product (e.g., hydrogen peroxide) generated from the first test line may flow toward the second test line or the control line, resulting in inaccurate results because the product (e.g., hydrogen peroxide) corresponding to the first test line may not be detected at the first test line but may be detected at the second test line or the control line.

[0058] Furthermore, electrochemical measurements are based on diffusion processes between electrodes 202a-f. With intact flow rates, convection is an additional factor in addition to diffusion that affects the current outcome of biochemical reactions. Thus, after a product (e.g., hydrogen peroxide) that can react with the electrodes and cause a current flow is generated at the control and / or test lines of porous medium 109, the product (e.g., hydrogen peroxide) is diluted with the surrounding buffer (e.g., acetate buffer). In this manner, if electrodes 202a-f come into contact with porous medium 109 after the product flows into absorbent pad 112, there may not be enough product to react with the metal in electrodes 202a-f and generate an electrical signal (e.g., by releasing electrons). Therefore, examples disclosed herein may (e.g., fully or partially) still (e.g., slowed, stopped, etc.) the flow rate to prevent and / or slow the product from migrating away from the test and / or control zones. In some examples, a mechanical device may be used to stop the flow of product toward the example absorbent pad 112 by severing (e.g., fully or partially) the example porous medium 109 at the example membrane sever 201, thereby stopping the flow of product. Additionally or alternatively, the flow of product may be stopped by applying a substance (e.g., adhesive, gel, chemical, etc.) to the porous membrane 109, activating a substance on the porous membrane 109, pinching the porous membrane 109, etc. In this manner, the product (e.g., hydrogen peroxide) remains in the corresponding test and / or control line and reacts with the metal of the electrodes 202a-f. While the example of FIG. 2D includes two membrane severances 201 (e.g., before the first test / control line and after the last test / control line), there may be membrane severances between different test / control lines, and / or the membrane severance before the first test / control line may be removed. An example of one or more mechanical devices for cutting the porous medium 109 to stop, slow, or otherwise resist flow is further described below in conjunction with Figures 2L-2R.

[0059] Additionally or alternatively, a mechanical device can apply compression to the porous media 109 to create barriers (e.g., along the lines indicated by membrane cuts 201) that act as a barrier to stop the flow of product (e.g., hydrogen peroxide) toward the absorbent pad 112. Additionally or alternatively, a chemical (e.g., adhesive, gel, oil, etc.) can be added to or contained on and / or within the porous membrane (e.g., along the lines indicated by membrane cuts 201) to act as a barrier to stop the flow of product toward the absorbent pad 112. Additionally or alternatively, any mechanism (e.g., mechanical, electrical, chemical, etc.) can be used to stop the flow of product (e.g., hydrogen peroxide) away from the test and / or control zones.

[0060] Also, as disclosed herein, in alternative examples, enzyme-free amperometric redox reactions can be used in the bioelectrochemical cells 111a-d. For example, the amperometric signal of the LFA device 104 can be measured without the GOx enzyme because the gold in the AuNPs can function as a catalyst. In such examples, thiosulfate can be used to improve the signal, as shown above in Processes 6-8. Furthermore, as shown above in Process 8, thiosulfate, ferricyanide, and KBr or KCl react, and the AuNPs catalyze the reduction to ferricyanide, generating an electronic signal.

[0061] 2D , electrode 202c contacts the T1 test zone, and electrode 202d contacts a non-test zone (e.g., the porous medium outside the PC, T1, and NC zones). In such an example, if a target analyte corresponding to T1 is present in the sample, when the sample is applied to the sample pad 106, the sample flows into the conjugate pad 108, binds to the conjugates and / or probes labeled with GOx, gold nanoparticles, and / or other label(s), and continues through the porous medium 109 to the waste pad 112. Because the target analyte is present in the sample, the target analyte attached to the GOx / gold nanoparticle-labeled conjugate / probe is immobilized in the test zone T1. Thus, after the porous medium 109 is saturated with the assay buffer (e.g., a threshold time after the assay buffer containing glucose and redox species is applied to the sample pad 106), the GOx / gold nanoparticles in test zone T1 oxidize glucose in test zone T1, generating a voltage drop (shown as U2 in FIG. 2D ) and / or current between test zone T1 and the area adjacent to the test zone where electrode 202d is located. The exemplary wireless chip 114 measures the voltage drop and / or current from electrode 202c to electrode 202d and determines that the target analyte is present if the voltage drop and / or current is above a threshold.

[0062] In operation, when the example of FIG. 2G is implemented in the LFA device 104 of FIG. 1A, a user or technician applies a sample (e.g., 25 microliters of urine, blood, etc.) to the exemplary sample pad 106. After sample application, the user or technician applies a biofuel-based buffer (e.g., six drops of an assay buffer containing glucose and a redox agent) to the sample pad 106 and / or a dedicated buffer pad. Once applied, the user waits the time threshold (e.g., 15 minutes) required for activation of the fuel cell in the porous medium 109. In other examples, the time threshold may be 20 minutes or some other value. In some examples, the time threshold is tracked using a software / application-based timer or a timer powered by the voltage and / or current generated on the porous medium 109. After the threshold duration, a user and / or technician interacts with the LFA device using the reader 116 to obtain diagnostic test results (e.g., by generating an electromagnetic field), which the wireless chip 114 of the LFA device 104 transmits to the reader 116 using the antenna 115 within the duration (e.g., within one minute). In some examples, the duration for reading the diagnostic test results can be other values, such as, for example, less than one minute or more than one minute (e.g., two minutes, three minutes, or more). In some examples, the reader 116 instructs the user to take action to stop the flow on the LFA device 114. In those examples, the reader 116 can instruct the user to take action after a threshold time (e.g., 15 minutes) but within a second duration (e.g., five minutes). In some examples, the reader 116 can instruct the user to scan the LFA device 104 to confirm that the correct LFA device was selected for shearing before the second duration (e.g., five minutes). The time required for the reader 116 to power the wireless chip 114, measure the electrical signal, and transmit the measurement signal can be 1 to 3 seconds. In some examples, the reader 116 prompts the user to confirm that action has been taken to stop the flow.The reader 116 then starts a clock, timer, and / or countdown for the duration (e.g., 1 minute) that the diagnostic test will be read. In some examples, the reader 116 provides a presentation on the user interface 120 indicating the time and duration as disclosed herein.

[0063] FIG. 2E shows a side view of the porous medium 109 of the machine-readable lateral flow immunoassay of FIG. 2D. In the example of FIG. 2E, the layer includes electrodes 202a-f in direct contact with the porous medium 109. In some examples, the electrodes are incorporated within a non-conductive layer, and the non-conductive layer including the electrodes 202a-f is placed (e.g., during manufacturing) in contact with the porous medium such that the electrodes 202a-f align as shown in FIG. 2D. In some examples, the electrodes 202a-f are each placed (e.g., during manufacturing) in contact with the porous medium 109 such that the electrodes 202a-f align as shown in FIG. 2D. In some examples, the electrodes 202a-f do not contact the porous membrane 109 until the device is ready to be read, as further described below in connection with FIGS. 2L-2R.

[0064] Figure 2F shows exemplary conjugates that may be attached to immobilized antigens, analytes, and / or antibodies on the test zone on the porous medium 109 of the machine-readable lateral flow immunoassay of Figures 2A-2E for an exemplary HIV test. Figure 2F shows an exemplary implementation 204. Additionally, Figure 2F includes an HIV-1 target analyte 206, a recombinant HIV-1 capture antigen 208, an HIV-2 capture antigen 210, an HIV-1 antibody, an HIV-1 antigen and glucose oxidase complex 211, a recombinant immobilized HIV-1 antigen 212, a recombinant immobilized HIV-2 antigen 214, and an antiserum 216.

[0065] During testing, a user and / or patient applies a patient biological sample and / or buffer solution via the sample pad 106. In the example of FIG. 2F, the sample includes an exemplary HIV-1 target analyte 206. The biological sample and / or buffer solution flows toward the exemplary absorbent pad 112 of FIGS. 1A and 1B. The exemplary conjugate pad 108 is pretreated with exemplary recombinant HIV-1 capture antigens 208 (e.g., gp41 and p24) and exemplary HIV-2 capture antigens 210 (e.g., gp36) that are coupled to (e.g., attached to, tagged with, etc.) glucose oxidase. Because the biological sample includes the exemplary target analyte 206 in FIG. 2F, the exemplary target analyte 206 attaches to the exemplary HIV-1 capture antigen 208 and glucose (e.g., corresponding to the formation of an exemplary HIV-1 antibody, HIV-1 antigen, and glucose oxidase complex 211), which is transported toward the absorbent pad 112. Test line 1 is coated with exemplary recombinant, immobilized HIV-1 antigens 212 (e.g., gp41 and p24), and test line 2 is coated with exemplary recombinant, immobilized HIV-2 antigens 214 (e.g., gp36). In the case of a positive patient sample containing HIV-1 antibodies 206, antibody-antigen-glucose oxidase complexes 211 bind to the recombinant HIV-1 antigens 212 immobilized on test line 1. However, because the biological sample does not contain the HIV-2 target analyte, nothing binds to test line 2. As described above, antigen-antibody complexes 211, which are coupled to an enzyme (e.g., glucose oxidase), generate a product (e.g., hydrogen peroxide) on test line 1 when the enzyme reacts with a buffer (e.g., glucose). The control line in FIG. 2F contains an exemplary antiserum 216 (e.g., goat anti-recHIV antiserum) that binds to the exemplary recombinant HIV-1 antigens 208.

[0066] Figure 2G shows the exemplary lateral flow immunoassay of Figures 2D-2E within an exemplary housing 222. The exemplary housing 222 houses the exemplary sample pad 106, exemplary conjugate pad 108, exemplary porous medium 109, exemplary waste pad 112, exemplary wireless chip 114, and exemplary antenna 115 of Figures 1A-2C. The exemplary housing 222 further houses the exemplary electrodes 202a-f of Figures 2D-2E. The exemplary housing 222 includes exemplary openings 223, 225 and exemplary layers 224, 226, 228.

[0067] The top layer 224 of the exemplary housing 222 in FIG. 2G includes exemplary openings 223, 225 that allow a user and / or technician to apply sample and / or buffer. In some examples, the sample is dispensed through opening 225, and the buffer is dispensed through opening 223, which is located closer to the edge of the housing 222. This allows the buffer to wash the sample from behind, since the lateral flow direction is left to right in the tester shown in FIG. 2G. Alternatively, the housing 222 may include a single opening for both sample and buffer. In some examples, openings 223, 225 include caps to protect against evaporation (e.g., of the sample and / or buffer). Additionally or alternatively, the housing 222 may include physical structures (e.g., foam pads) on the underside of the top and / or middle layers 224, 226 to apply uniform pressure to the porous medium 109 (e.g., via user interaction with the housing 222). In this way, the sample and / or buffer are evenly distributed throughout the porous medium 109. The second / middle layer 226 includes the wireless chip 114, the antenna 115, and the electrodes 202a-f. In some examples, the bottom of the top layer 224 includes pads to press the electrodes into contact with the porous medium 109 for a more complete connection between the electrodes 202a-f and sections of the porous medium 109.

[0068] In some examples, the middle layer 226 may further include additional electrodes to mitigate the risk of reading the LFA in the bottom layer 228 too early and / or too late. For example, the exemplary middle layer 226 may include an electrode (e.g., an anode) in contact with the waste pad 112 and / or an electrode (e.g., a cathode) in the waste pad that contacts the waste pad 112. The waste pad 122 may be impregnated with ascorbic acid, which, when saturated during a test, reacts with molecules in the waste pad 122 and generates a voltage, current, and / or electromotive force (e.g., depending on the different pH levels the electrodes are in contact with). In this manner, the wireless chip 114 may read the voltage and / or current difference between the electrodes in the waste pad 112 to determine whether the LFA-based test is ready and / or whether it has taken too long for the user to receive accurate results. For example, the anode electrode does not measure voltage, current, and / or EMF before the test is ready to be read, indicating that the dry citric acid has not been resuspended with the buffer and the test is not ready to be read. The anode electrode measures voltage, current, and / or EMF once the test is ready to be read, indicating that the dry citric acid has been resuspended with the buffer and the test is ready to be read. Furthermore, if the test is read too slowly, the resuspended citric acid will diffuse into the cathode area, offsetting the EMF, indicating that the test time has expired and there is no longer a consistent flow rate throughout the device to output an accurate result (e.g., the test can no longer be read). The bottom layer 228 of the housing 222 comprises an LFA material.

[0069] FIG. 2H illustrates an alternative exemplary implementation of the machine-readable lateral flow immunoassay 104 of FIG. 1A. As shown in FIG. 2H, the machine-readable lateral flow immunoassay 104 includes the porous medium 109 of FIG. 1 and exemplary quantum dots 230 positioned on an exemplary working electrode 232. The exemplary lateral flow immunoassay 104 further includes an exemplary working electrode 232, an exemplary counter electrode 234, and an exemplary reference electrode 236. The exemplary electrodes 232, 234, and 236 may be silver-carbon electrodes, copper electrodes, graphitic carbon electrodes, titanium electrodes, brass electrodes, platinum and palladium electrodes, ferrocyanide-doped screen-printed carbon electrodes, and / or any other type of electrode or combination of electrodes. The machine-readable lateral flow immunoassay 104 of FIG. 2H can be used in combination with the bioelectrochemical cell described above.

[0070] The exemplary quantum dots 230 in FIG. 2H function as conjugates on the exemplary LFA 104. Different quantum dots (e.g., zinc sulfide, lead sulfide, magnesium sulfide, copper sulfide, cadmium sulfide, etc.) may be present as process controls, negative controls, and / or corresponding to one or more target analytes. During manufacturing, the exemplary machine-readable LFA generator 102 can dissolve the quantum dots 230 in a weak acid or suitable solvent to produce dissolved quantum dots that are added to the conjugate pad of the LFA 104. In this manner, when a sample is applied to the LFA 104, target analytes corresponding to particular quantum dots attach to the quantum dots. As the quantum dots with attached target analytes flow toward the test zone of the porous medium, the quantum dots become immobilized by antigens, analytes, and / or antibodies in the test areas corresponding to one or more target analytes.

[0071] The exemplary working electrode 232 in FIG. 2 is in contact with the porous medium of the LFA 104. Thus, the working electrode 232 is in contact with the test area and any immobilized quantum dots (e.g., if a target analyte is present). To determine whether a target analyte is present, the wireless chip 114 or another device can perform a stripping voltammetry process. To set up a stripping voltammetry process, the wireless chip 114 or other voltage source applies a voltage to the working electrode 232 for a specific time (e.g., 60-180 seconds) to deposit (e.g., coat) the immobilized quantum dots on the working electrode 232. After the quantum dots are deposited on the working electrode 232, the wireless chip 114 can perform the stripping voltammetry process for a duration (e.g., 60-240 seconds). Stripping voltammetry involves changing the voltage potential between the counter electrode 234 and the reference electrode 236, resulting in a change in current and / or voltage if the quantum dots are deposited on the working electrode 232. The wireless chip 114 determines that the target analyte is present when a change in current and / or voltage above a threshold amount is measured.

[0072] 2I-2K illustrate example front-end channels 240, 250, 260 interfacing between the example bioelectrochemical cells 111a-d of FIGS. 1A, 1B, 2A, and / or 2B and the wireless chip 114 of FIGS. 1A, 2A, and / or 2B. Additionally or alternatively, the example front-ends 240, 250, 260 can interface between the electrodes 202a-f, 234, 236 of FIGS. 2D, 2E, and / or 2H and the wireless chip 114. While the example front-ends 240, 250, 260 may be implemented as components external to the wireless chip 114, the front-ends 240, 250, 260 may also be implemented within the wireless chip 114 and / or as part of a separate device. If the example wireless chip 114 is implemented in a standalone device (e.g., separate from the LFA 104), the example front ends 240, 250, 260 may be implemented in the LFA 104 and / or in the device that includes the wireless chip 114.

[0073] The example front-end channel 240 of FIG. 2I functions as an electronic multiplexer, a bank of MOSFETs, and / or any other electronic circuitry to transmit the signals received from each of the bioelectrochemical cells 111a-d to four inputs of the wireless chip 114. The example wireless chip 114 outputs control signals to the example front-end 240 that control which bioelectrochemical cell's signal needs to be processed at different times. While the wireless chip 114 of FIG. 2I includes four inputs (e.g., very high, high, low, and very low), the wireless chip 114 can include any number of inputs corresponding to any number of levels. The four inputs of the wireless chip 114 compare the magnitude of the resulting signal to preset thresholds to identify the amount of measured voltage or current. For example, if the output of bioelectrochemical cells 111a-d is a voltage (e.g., that of a potentiometric sensor), the first input can compare the magnitude of the resulting voltage to 80 mV, the second input can compare the magnitude of the resulting voltage to 60 mV, the third input can compare the magnitude of the resulting voltage to 40 mV, and the fourth input can compare the magnitude of the resulting voltage to 20 mV. Thus, if front end 240 outputs a 70 mV signal from first bioelectrochemical cell 111a, wireless chip 114 can determine, based on those comparisons, that the resulting signal is high (e.g., greater than 60 mV) but not very high (e.g., not greater than 80 mV). Wireless chip 114 can transmit the determined output strength for each measurement (e.g., very high, high, low, or very low) to exemplary LFA reader application 117. In this manner, the results can be further analyzed (e.g., in the reader 116 and / or another external device, database, server, or data center) to identify patterns, to identify test accuracy, and / or for device monitoring purposes.

[0074] 2J is an alternative implementation that functions as a multiplexer and / or demultiplexer to transmit received (e.g., accessed, acquired, etc.) signals from each of bioelectrochemical cells 111a-d to a corresponding input of wireless chip 114. For example, front-end channel 250 ensures that first bioelectrochemical cell 111a is output to a first input, second bioelectrochemical cell 111b is output to a second input, etc. For example, front-end channel 250 can be implemented using a multiplexer and demultiplexer, where select lines of the multiplexer and demultiplexer can be coupled together to ensure that a first output of bioelectrochemical cell 111a is sent to a first input of wireless chip 114, a second output of bioelectrochemical cell 111b is sent to a second input of wireless chip 114, etc. The example wireless chip 114 outputs one or more control signals to example front-end 240 that control which bioelectrochemical cell's signals need to be processed at different times. In some examples, the front-end channel 250 may include a multiplexer controlled to sample / measure each of the electrodes at different times, with each measurement passed to a single comparator or analog-to-digital converter on the wireless chip 114. In this manner, all results can be obtained using a single component on the wireless chip 114. In some examples, the front-end 250 is controlled to make multiple measurements of each test line and multiple measurements of each control line. For example, the front-end 250 may be controlled to make multiple measurements of the test line, the control line, and the wireless chip 114 transmitting the results to the reader 116 and / or performing statistical preprocessing of the measurements before transmitting the data to the reader 116. While the wireless chip 114 of FIG. 2J includes four inputs (e.g., for the four bioelectrochemical cells 111a-111d), the wireless chip 114 may include any number of inputs corresponding to any number of cells, controls, and / or electrodes.2J, the input of wireless chip 114 determines the amount of current and / or voltage (e.g., as a digital value) corresponding to first bioelectrochemical cells 111a-111d. Wireless chip 114 can transmit the determined output intensity for each measurement to exemplary LFA reader application 117.

[0075] The example front-end channel 260 of FIG. 2K is an alternative implementation corresponding to a direct channel between each of the bioelectrochemical cells 111a-d and the corresponding input of the wireless chip 114. For example, the first output of the bioelectrochemical cell 111a is directly coupled to the first input of the wireless chip 114 via the first channel, the second output of the bioelectrochemical cell 111b is directly coupled to the second input of the wireless chip 114 via the second channel, etc. Although the wireless chip 114 of FIG. 2K includes four inputs (e.g., for the four bioelectrochemical cells 111a-d), the wireless chip 114 can include any number of inputs corresponding to any number of cells, controls, and / or electrodes. In the example of FIG. 2K, the inputs of the wireless chip 114 determine the amount of current and / or voltage (e.g., as a digital value) corresponding to the first bioelectrochemical cell 111a-d. The wireless chip 114 can transmit the determined output strength for each measurement to the example LFA reader application 117.

[0076] While the example wireless chip 114 of FIGS. 2I, 2J, and 2K includes a comparator that compares the resulting voltage and / or current magnitude to a threshold and transmits a result corresponding to the comparison, the example wireless chip 114 may also include an analog-to-digital converter that converts the analog voltage and / or current readings to digital values ​​and transmits the digital values ​​to the example reader 116. In this manner, the example reader 116 may compare the digital values ​​to one or more thresholds to determine a result. In some examples, the wireless chip 114 may obtain multiple voltage and / or current measurements (e.g., voltage samples, current samples, etc.) for each test line and control line, convert those measurements to digital values, and transmit all digital values ​​to the example reader 116. In some examples, the wireless chip 114 may perform preprocessing of those values ​​(e.g., statistical analysis such as determining the mean, median, mode, standard deviation, etc. of the multiple measurements) and transmit one or more value(s) representing the multiple measurements to the reader 116.

[0077] 2L-2O illustrate examples of halting (e.g., stopping and / or slowing) the flow of liquid (e.g., including generated products such as hydrogen peroxide) toward an absorbent or waste pad. As described herein, the flow can be halted to allow an amount of generated product (e.g., hydrogen peroxide) to accumulate or otherwise reside in the test line, react with an electrode in contact with the test line, and generate a measurable electrical signal. In some examples, the electrode can move to contact the test line to react after the flow is halted. In some examples, the electrode moves to contact the test line when a flow stop mechanism is deployed or activated. FIGS. 2L-2O include portions of the LFA device 104 in a flow position (e.g., FIGS. 2L and 2N) and a read position (e.g., FIGS. 2M and 2O). In the flow position of the LFA device 104, chemical mixing and reactions as disclosed herein occur, and elements and / or products flow along the porous medium 109, e.g., FIG. 1A. In the read position, electrodes 202a-f of Figure 2D are applied to porous medium 109 to initiate the read phase for the diagnostic test. The example of Figures 2L-O includes an example switch 278, one or more example flow arresters 280, and an example electrode substrate or chip 282.

[0078] The example switch 278 of Figures 2L-O is a component or device that moves between a first position (e.g., a flow position shown in Figures 2L and 2N) and a second position (e.g., a read position shown in Figures 2M and 2O). In some examples, the switch 278 slides within a groove or track 279 within the housing 222 of the LFA device 104. In some examples, the switch 278 slides, translates, or otherwise moves between the first and second positions within the LFA device 104. For example, the switch 278 can be depressed downward to contact the porous media 109.

[0079] The switch 278 includes an example positionable flow arrestor 280 that can be positioned to slice, cut, shear, and / or compress the example porous medium 109 (e.g., corresponding to the example membrane cutter 201 in FIG. 2D ) when the switch 278 moves from a first position to a second position. In some examples, the flow arrestor 280 includes one or more blades that cut (e.g., partially or completely) the porous medium 109. In some examples, to partially cut the porous medium 109, the blades cut partially within the depth of the porous medium. In some examples, a portion of the depth (e.g., a lower portion) of the porous medium 109 is left uncut. In some examples, the flow arrestor 280 includes one or more ridges for pressing into the porous medium 109. In some examples, the flow rate is stopped by applying a chemical (e.g., adhesive, gel, oil, etc.) to the porous medium 109 at one or more of the locations where the flow arrestor 280 contacts the porous medium 109. In some examples, the chemical may be structured to release for a duration after the liquid sample or buffer is applied (e.g., the time the chemical is wetted by the liquid sample or buffer) that corresponds to the time that flow must be stopped to prevent product (e.g., hydrogen peroxide) from flowing away from the test and / or control zones.

[0080] In the illustrated example, there are two flow arresters 280. In some examples, there are other numbers of flow arresters 280, such as one, three, etc. In some examples, if there is one flow arrester, the flow arrester is positioned to compress, cut, or shear the porous medium 109 between the location where the electrode(s) 202a-202f contact the porous medium 109 and the absorbent pad 112, separating the absorbent pad 112 and preventing further absorption of the product (e.g., hydrogen peroxide) through the porous medium 109. In some examples, a second flow arrester 280 can be used to prevent backflow of liquid toward the conjugate pad 108.

[0081] The switch 278 is initially positioned in a first position (e.g., away from the porous medium 109). When a sample is applied to the LFA device 104, the sample flows across the porous medium 109 as described herein. If a target analyte is present in the sample, a chemical reaction occurs and a product (e.g., hydrogen peroxide) is released at the target zone. For a duration after the sample is applied, the reader 116 can instruct (e.g., command, prompt, etc.) the user to move the switch 278 from the first position to the second position (e.g., on the porous medium 109) such that the example flow arrestor 280 can cut, shear, and / or compress (e.g., pinch) the porous medium 109 to stop or reduce the flow of the mixture, including any mobilized product (e.g., hydrogen peroxide), if present, corresponding to the flow of electrons. In some examples, the switch 278 can release a substance (e.g., oil, glue, gel, etc.) along a line on the porous membrane 109 corresponding to the membrane break 201, where the substance acts as a barrier to stop the flow of the product (e.g., hydrogen peroxide) and allow the current flow rate. In some examples, the substance can be structured to release for a duration after the liquid sample or buffer is applied (e.g., while the liquid sample or buffer is wetting the substance), corresponding to the time the flow rate needs to be stopped to prevent the product (e.g., hydrogen peroxide) from flowing away from the test and / or control zone. The product remains in the area of ​​the porous medium 109 between the flow arresters 280. In this way, the product (e.g., hydrogen peroxide) can react with the metal of the electrode(s) 202a-202f present in this area of ​​the porous medium 109. The reaction of the product with the electrodes 202a-202f generates an electrical signal (e.g., by releasing electrons) that can be read by the exemplary wireless chip 114 to determine whether the target analyte is present in the sample. In some examples, if the electrode is in contact with the porous membrane 109 when a product (e.g., hydrogen peroxide) is being generated, the electron flux may be lower and / or inconsistent, potentially corresponding to a false negative or false positive test result.Thus, after a duration allowing a product (e.g., hydrogen peroxide) to be produced, the electrodes can be placed in place (e.g., in contact with the porous membrane 109). For example, after sufficient time has passed for glucose oxidase and glucose to react to produce the product hydrogen peroxide, the switch 278 contacts the exemplary electrodes 202a-202f so that the amount of product is sufficient to react with the electrode(s) 202a-202f after the flow has stopped and generate an electrical signal strong enough to be measured without the need for an external power source. In other words, by allowing the electrodes to contact the porous membrane 109 for the appropriate time, a sufficiently strong signal is generated without the need for an external power source, so that an external power source is not required to provide a potential that makes it easy to read the electrical signal from the reaction at the electrodes. Having the electrodes in contact with the porous membrane 104 while the test glucose and glucose oxidase are reacting would result in a smaller electrical signal, making it more difficult to sense. In some examples, the switch 278 can be configured to lock into two preset positions (e.g., a flow position and a read position). In this way, the user is less likely to accidentally move switch 278 and / or more likely to perform a complete share when commanded by reader 116. For example, switch 278 may include a mechanism that holds the switch in the flow position and / or the read position until a threshold amount of force is applied or until switch 278 is adjusted out of the locked position. In some examples, when switch 278 is moved out of the flow position and / or when switch 278 is moved to the read position, a clicking noise is generated to provide an audible indication to the user that the position of switch 278 has moved and / or that the switch movement is complete.

[0082] The exemplary electrode substrate 282 of FIG. 2L is a circuit board including electrodes 202a-202f of FIG. 2D. In a first position of switch 278, electrode substrate 282 is positioned at an angle relative to porous media 109 and / or switch 278. LFA device 1045 includes an exemplary LFA support 283 within housing 222. Support 283 includes an angled slot 284 that accommodates electrode substrate 282 at an angle relative to the horizontal direction of porous media 109 when the LFA device is in the flow-through position. In this manner, electrodes 202a-f on exemplary electrode substrate 282 are not in contact with porous media 109. When a user moves switch 278 to a second position, the angle of electrode substrate 282 changes due to movement of switch component 278 and ridge or fulcrum 286 on LFA support 283. For example, movement of switch 278 pushes electrode substrate 282, rotating it about fulcrum 286 toward porous medium 109 until it contacts porous medium 109 (e.g., a second or read position). In the second position, electrode substrate 282 is parallel to and / or in contact with porous medium 109 and / or switch 278. In this manner, if electrodes 202a-202f are present in the area of ​​porous medium 109 between flow arrestors 280 and are able to react with a product, this product can react with the electrodes to generate electrons, and wireless chip 114 can measure the current and / or voltage difference corresponding to these electrons to determine whether a target analyte is present in the sample. If electrode substrate 282 is not in contact with porous membrane 109 while reader 116 is attempting to read a result, there will be no indication from the electrodes corresponding to the control zone or line. Thus, if the user does not move switch 278 to the read position, electrodes 202a-202f will not contact porous membrane 109 and an error will be output to the user when reader 116 attempts to read the results. In some examples, electrode substrate 282 is pivotable.In such examples, when a user can move and / or pivot a switch, the exemplary electrode substrate 282 pivots into position (e.g., in contact with the porous membrane) while stopping the flow of fluid over the porous membrane 282 (e.g., using the exemplary flow arrestor 280).

[0083] In some examples, instead of or in addition to the example flow arrestor 280 implemented on the example switch 278, one or more of the flow arrestors 280 can be implemented within the electrode substrate 282. In this manner, when the electrode substrate 282 is moved toward the porous medium 109, the flow arrestor 280 of the electrode substrate 282 can compress, cut, and / or shear the porous medium 109, stopping or reducing the flow rate of the mixture toward the absorbent pad 112. In the second position, the example switch 278 holds the electrode substrate 282 in place ensuring that the electrodes 202a-202f remain in contact with the porous medium 109. In some examples, a ridge or fulcrum 286 helps secure the electrode substrate 282 in the first or second position.

[0084] In some examples, the electrode substrate 282 is integral with the switch 278. For example, the face of the switch 278 facing the porous medium 109 in the second or read position can include the electrode substrate 282 such that the electrodes 202a-202f are pressed into and / or otherwise contact the porous medium 109 when the switch 278 is moved to the second position. In some examples, the electrode substrate 282 may be positioned on the switch offset outward from the flow arrestor 280 such that the flow arrestor 280 contacts the porous medium 109 and stops the flow before the electrode substrate 282 contacts the porous medium 109. In other examples, the electrode substrate 282 and the flow arrestor 280 are aligned on the switch 278.

[0085] While the exemplary switch 278 compresses, cuts, and / or shears the porous medium 109 and the electrode substrate 282 in contact with the porous medium 109 in response to a sliding motion from a user, the exemplary switch 278 may be structured to compress, cut, and / or shear the porous medium 109 and / or move the electrode substrate 282 in contact with the porous medium 109 in other manners, including, for example, automatically, via a pressing motion, and / or any other user and / or processor controlled manner.

[0086] FIG. 2P shows a perspective view of LFA device 104 including an alternative exemplary switch 292. FIG. 2Q is a partial cross-sectional view of the LFA device taken along line QQ of FIG. 2P. In FIG. 2Q, LFA device 104 is rotated 180 degrees compared to FIG. 2P, with a portion of the top plate shown in dashed-dot lines and another portion removed along line QQ to reveal the interior of LFA device 104. FIG. 2R is a partial cross-sectional view of the LFA device taken along line RR of FIG. 2P. LFA device 104 is oriented in the same direction in FIG. 2R as in FIG. 2Q. Switch 292 includes an exemplary grip or actuator 293. Actuator 293 allows a user to move switch 292 between a first position (e.g., a flow position) and a second position (e.g., a read position). Exemplary switch 292 also includes flow arrestor 280, as disclosed above. In the illustrated example, flow arrestor 280 is coupled to or positioned on the opposite side of switch 292 from actuator 293.

[0087] FIG. 2Q shows the example switch 292 in a first position (e.g., a flow position) in which the flow arrestor 280 is positioned away from the porous medium 109. In this position, the example electrode 202a is not in contact with the test line of the porous medium 109. When the test is ready to be read, the user presses, translates, slides, or otherwise moves the actuator 293, causing the switch 292 to move to the read position (e.g., above the porous medium 109). In this position, the flow arrestor 280 compresses, cuts, and / or shears the porous medium 109, reducing or stopping the flow of fluid along the porous medium 109. In this manner, any products (e.g., hydrogen peroxide) generated along the porous medium 109 in the area between where the flow arrestor 280 contacts the porous medium 109 remain in this area and near or at the corresponding test and / or control lines. Additionally, moving the switch 292 causes the electrode 202a to contact the test line of the porous medium 109. In this manner, when a product (e.g., hydrogen peroxide) at the test line is able to react with electrode 202a, measurable electrons corresponding to a positive test result can be emitted. In the example of Figures 2P-R, a user moves actuator 293 in a sliding motion to operate switch 292 and flow arrestor 280. In other examples, other actuations can be used, including automatic movements, pressing, squeezing, and / or any other user and / or processor control.

[0088] In some examples, the LFA device 104 and / or housing 222 of FIGS. 2G, 2L-2R can include a compartment containing a holding device (e.g., a bag) that holds a liquid (e.g., a second buffer solution). The holding device can be positioned near the porous medium 109. In such examples, a mechanical device (e.g., switch 278, one or more of flow arresters 280, electrode substrate 282, switch 292, and / or another device) can be used to break the holding device and / or otherwise cause the liquid contained therein to be released into the holding device. In this manner, the liquid can rebuffer the porous medium 109, changing the buffer conditions to an optimal and / or improved state for antigen coupling and providing a more reliable and / or valid electronic readout. The fluid stored in the holding device (e.g., a second buffer solution different from the buffer applied to the sample pad of the LFA) can be different from the buffer applied after the sample is applied. For example, the second buffer stored in the holding device may contain antibodies and / or antigens that facilitate the reaction of glucose and glucose oxidase to help optimize and / or improve the electrochemical readout (e.g., current and / or voltage output in the presence of the target analyte). Additionally or alternatively, the LFA reader 116 may instruct (e.g., command, prompt, etc.) the user to add additional buffer to the LFA device to increase the reliability and / or effectiveness of the electronic readout.

[0089] 3A shows an alternative exemplary machine-readable LFA device 300 that may be generated by the exemplary LFA generator 102 and / or read by the exemplary machine-readable LFA reader application 117 of the reader 116. The exemplary LFA device 300 implements a circuit-complete technique for determining a test result based on an electrical signal. The exemplary machine-readable LFA device 300 is a circuit-complete LFA that includes the exemplary sample pad 106, exemplary conjugate pad 108, exemplary porous medium 109, exemplary test area 110, exemplary absorbent pad 112, exemplary wireless chip 114, and exemplary antenna 115 of FIG. 1A. The exemplary machine-readable LFA device 300 further includes exemplary test / control lines 302, 304, 306, an exemplary first electrode 308a, and an exemplary second electrode 308b.

[0090] 3A, the exemplary conjugate pad 108 includes conjugates and / or probes (e.g., antigens and / or antibodies) labeled with gold nanoparticles. The conjugates and / or probes correspond to target analytes corresponding to one or more condition(s) or disease(ies). In this manner, when a sample is applied to the sample pad 106, if the sample contains the target analyte, the corresponding gold-labeled conjugate will bind to the target analyte and flow toward the absorbent pad 112.

[0091] The test zone(s) and / or control zone(s) 302, 304, 306 in Figure 3A extend from one side of the porous medium 109 to the other side of the porous medium 109. The test zone(s) and / or control zone(s) 302, 304, 306 contain immobilized antigens and / or antibodies corresponding to one or more target analytes. In this manner, if the target analytes are present in the sample, the target analytes (bound to the gold-labeled conjugates) will bind to the corresponding test and / or control lines 302, 304. After the sample is applied, the user applies a wash solution containing an autocatalytic silver component (e.g., a solution containing silver ions and a reducing agent such as hydroquinone, aminophenol, or ascorbic acid) to the sample pad 106 or another sample pad. In some examples, the sample pad 106 (or another pad or inlet) can contain silver nitrate, and the reducing agent can be located in a separate paper / membrane that can be attached to the LFA medium after development (e.g., via a mechanical structure that separates the two membranes but allows user intervention to attach the two membranes (e.g., a user and / or automated structure can apply force to the mechanical structure to push the two membranes into contact)).

[0092] As the wash solution flows toward the absorbent pad 112 of FIG. 3A, the silver binds to the immobilized gold, amplifying the size of the immobilized metal in the test and / or control lines 302, 304. When the silver is sufficiently amplified, the silver molecules attached to each immobilized gold nanoparticle come into contact, creating a short circuit (e.g., closing an electrical switch and acting as a resistive element, such as a resistor). In this manner, a voltage can be applied to exemplary electrode 308a at one end of test and / or control lines 302, 304, 306, and then, if the target analyte is present, the silver amplification creates a short circuit with some resistance to second electrode 308b at the other end of test and / or control lines 302, 304, 306, allowing current to flow from electrode 308a to electrode 308b through the silver-amplified gold nanoparticles, which act like a conductivity enhancer (e.g., a small resistor). The exemplary wireless chip 114 measures current, voltage, electromotive force, and / or resistance to determine whether the target analyte is present (e.g., whether a current above a threshold or a resistance below a threshold is sensed between electrodes 308a, 308b). The exemplary wireless chip 114 can test each of lines 302, 304, 306 in series or in parallel. An exemplary illustration of the silver amplification process is further disclosed below in connection with FIG. 3B.

[0093] Figure 3B illustrates an exemplary circuit completion process for the exemplary machine-readable LFA device 300 of Figure 3A, with a target analyte attached to the exemplary test line 302 of Figure 3A. The example of Figure 3A includes the exemplary porous medium 109, exemplary test line 302, and exemplary electrodes 308a, 308b of Figure 3A. The example of Figure 3B further includes an exemplary immobilized antibody / antigen 310, exemplary gold nanoparticles 312, exemplary conjugated antibody / antigen 314, exemplary target analyte 316, and exemplary amplified silver 318. Alternatively, the example of Figure 3B may be described in combination with any of lines 302, 304, 306 of Figure 3A.

[0094] In Stage 1, the exemplary immobilized antibody 310 of the exemplary test line 302 is attached to the exemplary target analyte 316. As shown in FIG. 3B, the target analyte 316 is attached to the exemplary conjugated antibody and / or antigen 314, which is labeled with gold nanoparticles 312. However, the gold nanoparticles 312 are too small to touch each other. Therefore, when a voltage is applied to one of the electrodes 308a, 308b, no current flows (e.g., they function as an open switch). Therefore, a wash solution containing a silver ion solution is applied to the porous medium 109. The silver in the wash solution amplifies (e.g., accumulates via autocatalysis) at the gold nanoparticles 312, as shown in Stage 2. When a sufficient amount of silver is amplified (e.g., by reduction of silver using a reducing agent (e.g., autocatalysis)), a short circuit occurs from electrode 308a to electrode 308b (e.g., they function as a closed switch with some resistance). In this manner, when the wireless chip 114 applies a positive voltage to electrode 308b, a current flows to exemplary electrode 308a (e.g., through the silver contacts). The exemplary wireless chip 114 senses the current and determines that the target analyte 316 is present in the sample.

[0095] 4 is a block diagram of an example implementation of the machine-readable LFA generator 102 of FIG. 1A. The example machine-readable LFA generator 102 includes an example user interface 400, an example portion generator 402, and an example portion applicator 404.

[0096] 4 interfaces with a user and / or manufacturer to obtain instructions regarding how to structure the machine-readable LFA device 104, 300. For example, the user interface 400 may receive instructions regarding the type of machine-readable LFA device that needs to be produced, the number of test zones (e.g., in the case of a multiplexed LFA design) and / or test types that the LFA device 104, 300 should perform, and / or the number of control zones and / or types that should be included within the LFA device 104, 300 (e.g., to access, to obtain, etc.).

[0097] 4 generates and / or retrieves portions of the exemplary LFA device 104, 300. For example, the portion generator 402 can generate and / or retrieve the sample pad 106, conjugate pad 108, porous medium 109, antibodies, antigens, and / or molecules from storage and apply them to the LFA device 104, 300, absorbent pad 112, wireless chip 114, antenna 115, connections, housing, and / or bioelectrochemical cells 111a-n. To generate a bioelectrochemical cell, the exemplary portion generator 403 can impregnate a paper strip or other substrate with an enzyme substrate (e.g., glucose) and / or a reducing agent (e.g., hydroquinone, aminophenol, ascorbic acid (e.g., vitamin C), etc.), and / or an electron mediator or redox species (e.g., potassium ferricyanide, ferrocene, oxygen, ferrocene derivatives, etc.), and the paper can be dried, for example, via air drying.

[0098] The example portion applicator 404 of FIG. 4 applies the obtained and / or generated portions based on user instructions and / or manufacturing instructions to produce the example machine-readable LFA device 104, 300 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2H, 2L-2R, and / or 3A. For example, the portion applicator 404 can apply antigens and / or antibodies attached to GOx, silver nitrate, a reducing agent, and / or gold to the obtained and / or generated conjugate pad 108. In the case of a gold nanoparticle amplification approach, silver nitrate may be added to a second pad along with glucose (e.g., a fuel and / or enzyme substrate), or a reducing agent may be impregnated into the cell paper / medium. Furthermore, the portion applicator 404 structures the portions of the machine-readable LFA device 104, 300 to apply antigens and / or antibodies corresponding to the number of tests, type of tests, number of controls, and / or type of controls within the test and / or control zones of the test area 110 on the porous medium 109.

[0099] 5 is a block diagram of an example implementation of the wireless chip 114 of FIGS. 1A, 2A, 2B, 2G, 2I-2K, and / or 3 A. The example wireless chip 114 includes an example antenna interface 500, an example driver 502, an example sensor 504, an example comparator 506, example result storage 508, an example timer 510, and an example analog-to-digital converter 512.

[0100] The example antenna interface 500 of FIG. 5 interfaces with the example antenna 115. For example, when a magnetic field is within a threshold range of the antenna 115, the antenna 115 generates a current from the magnetic field and uses this current to power the example wireless chip 114. Thus, in some examples, the LFA device 104 does not include an accumulator (e.g., a battery that stores energy) that does not use an external supply of one or more reactants to generate a voltage. Thus, the example LFA device 104 is battery-less. For example, the LFA may be powered by an electromagnetic signal obtained from the antenna 115 (e.g., generating a voltage based on an electromagnetic signal generated by an external device or reader) or one or more of the bioelectrochemical cells 111a-d (e.g., generating a voltage based on a chemical reaction caused by oxidation in a test zone by a target analyte attached to an antigen or antibody labeled with GOx and / or gold nanoparticles). In some examples, the wireless chip 114 may include a battery for powering the wireless chip 114. Additionally, once results (e.g., flags or logical values ​​of one or more tests and / or controls) are obtained, the antenna interface 500 may interface with the antenna 115 to transmit the results (e.g., flags) and / or any identification information (e.g., an LFA identifier) ​​to the exemplary reader 116.

[0101] The example driver 502 of Figure 5 is a voltage driver that outputs a voltage to the electrode 308a of Figure 3A. As disclosed above, the wireless chip 114 outputs a voltage to determine, via circuit completion (e.g., silver amplification), whether the test zone has developed a short, which indicates a positive result for the test analyte. Thus, the example driver 502 responds to a short and positive result by outputting a voltage to the top electrode 308a (e.g., in series or parallel) and determining whether the sensor 504 can measure a current and / or a small resistance at the corresponding bottom electrode 308b. In some examples, the driver 502 controls the front-end channels 250, 260 to toggle between the electrodes.

[0102] 5 may be a voltage sensor, a current sensor, an electromotive force sensor, or a resistance sensor. For example, in the case of the fuel-based LFA device 104 of FIGS. 1A, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R, the example sensor 504 is a voltage and / or current sensor that measures the voltage drop across and / or current between one or more of the bioelectrochemical cells 111a-n by sensing the voltage drop and / or current from a first pin coupled to the top of the bioelectrochemical cell and a second pin coupled to the bottom of the bioelectrochemical cell. In another example, in the case of the circuit-complete LFA device 300 of FIG. 3A, the example sensor 504 is a current sensor that measures the amount of current passing through the test lines 302, 304 and / or the control zone 306 by sensing the current from a first pin coupled to the first electrode 308a to a second pin coupled to the corresponding second electrode 308b. In another example, the exemplary sensor 504 is an electromotive force sensor that measures the electromotive force between the first electrode 308a and the second electrode 308b and / or measures the electromotive force between a first pin coupled to a first portion of the bioelectrochemical cell and a second pin coupled to a second portion of the bioelectrochemical cell. If the exemplary sensor 504 is a resistance sensor, the sensor 504 measures the resistance from a first pin coupled to a first electrode 308a to a second pin coupled to a corresponding second electrode 308b.

[0103] 5 compares the sensed resistance, current, and / or voltage of each test zone and / or control zone to a threshold amount of resistance, voltage, and / or current. The example comparator 506 may be a software-based comparator (e.g., comparing a digital and / or analog voltage and / or current value to a threshold), a firmware-based comparator, and / or a hardware-based comparator (e.g., inputting a digital and / or analog voltage and / or current to a first input and a threshold voltage and / or current to a second input and outputting a logic value corresponding to whether the first input is higher or lower than the second input). For example, if the sensor 504 determines a voltage drop across a first bioelectrochemical cell (e.g., bioelectrochemical cell 111a), the example comparator 506 compares the voltage to a threshold (e.g., 50 mV). If the comparator 506 determines that the voltage exceeds the threshold, the comparator 506 outputs a first logic value (e.g., "1") and / or otherwise flags the result as a positive result for the corresponding target analyte and / or control zone. If the exemplary comparator 506 determines that the voltage is below the threshold, the comparator 506 outputs a second logic value (e.g., "0") and / or otherwise flags the result as a negative result for the corresponding target analyte and / or control zone.

[0104] 5 stores those results (e.g., flags and / or logical values ​​corresponding to the test zones and / or control zones). Additionally, the result storage 508 can store identifiers (e.g., device identifiers, machine-readable identifiers for the number and / or type of tests and / or controls used in the LFA device 104, 300, etc.). In this manner, the antenna interface 500 can include the identifiers with the results when transmitting those results to the reader 116.

[0105] As disclosed herein, the results of the test are read at a specific time and / or within a specific time window that allows for the chemical reactions disclosed herein. Accordingly, in some examples, the wireless chip 114 includes a timer 510. The example timer 510 of FIG. 5 tracks the time since one or more of the bioelectrochemical cells 111 a-n have been activated (e.g., since generating a voltage). For example, the bioelectrochemical cells 111 a-n may apply the generated voltage of an LFA-based test to the example wireless chip 114 to power the wireless chip 114 while the test is being performed. Once powered with the voltage generated by one or more of the bioelectrochemical cells 111 a-n, the timer 510 can start a wait timer to help identify when the LFA test is ready to be read. For example, the comparator 506 can compare the wait time to an assay time (e.g., a threshold corresponding to the time when the LFA test is ready to be read). In this manner, if the reader 116 attempts to read the LFA 104 before the LFA 104 is ready, the wireless chip 114 can transmit timing information to the exemplary reader 116 so that the reader 116 can determine that the test is not ready and / or can determine when the test will be ready to read.

[0106] 5 converts analog voltage and / or current values ​​obtained (e.g., sensed) from the sensor 504 into digital voltage and / or current values. In this manner, the example antenna interface 500 can transmit the digital values ​​to the example reader 116.

[0107] 6 is a block diagram of an example implementation of the machine-readable LFA reader application 117 of FIG. 1A for reading the LFA devices of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, 2L-2R, and / or 3 A. The example machine-readable LFA reader application 117 includes an example component interface 600, an example result determiner 602, an example test type storage 604, an example result storage 606, and an example timer / counter 608.

[0108] 6 interfaces with other components of the exemplary reader 116. For example, the component interface 600 can send prompts, text, and / or images to the exemplary user interface 120 for display to the user. Additionally, the exemplary component interface 600 receives (e.g., accesses, retrieves, etc.) data entered by a user via the user interface 120. For example, if a user enters identification information, patient information, demographic information, etc. into the user interface 120, the exemplary component interface 600 retrieves the entered information from the user interface 120. Additionally, the exemplary component interface 600 interfaces with the antenna 118 and controls the antenna 118 to output a magnetic field that can wirelessly power the exemplary wireless chip 114 via the exemplary antenna 115 and wirelessly receive (e.g., access, retrieve, detect, etc.) data (e.g., test results, identifiers, etc.) from the exemplary wireless chip 114. In some examples, component interface 600 interfaces with a camera to obtain identification information via a photograph and / or scan (e.g., a QR code, a barcode, etc.) of LFA device 104. In some examples, component interface 600 interfaces with a transmitter (e.g., corresponding to exemplary antenna 118 and / or another transmitting device) of reader 116 to transmit LFA-based test reading results to an entity that monitors those results. For example, component interface 600 and the transmitter can transmit the results over a network to an external or remote location for inclusion within an ERM and / or to other medical facilities, government agencies, NGOs, etc.Those results may include which tests / controls were positive, which tests / controls were negative, the identity of the LFA device or test and / or control used, and / or contextual or supplemental information obtained from the reader 116 and / or the user (e.g., timestamp, location data from a global positioning system sensor on the reader 116, patient information and / or demographics, lot number, use-by date, expiration date, test information, signal quality information, chain of custody, operator information, etc.). In this manner, if the entity monitoring those results determines that a particular LFA device has been used beyond a threshold percentage number, the LFA device may be flagged as a possible counterfit, and subsequent action can be taken to prevent further counterfits and / or reliance on test results from counterfit devices. If network connectivity is unavailable after the tests are performed, the component interface 600 can transmit the results after receiving an indication that network connectivity is available.

[0109] 6 determines whether a test is ready and / or the test result based on the obtained results and / or the identification information. For example, if the identification information is not known, the example result determiner 602 obtains the identification information from the wireless chip 114. Additionally or alternatively, the example result determiner 602 can obtain the identification information by scanning a QR code on the LFA device 104 using a camera or by prompting a user to manually enter a code on the LFA device 104. The result determiner 602 can then access the number of tests, type of tests, number of controls, and / or type of controls used on the LFA device 104, 300 from test type storage 604 (e.g., which stores identification information along with the corresponding number of tests, type of tests, number of controls, and / or type of controls used on the LFA device 104, 300) based on the identification information (e.g., device identifier, test and / or control structure identifier, etc.).

[0110] In some examples, the result determiner 602 authenticates the LFA device 104 based on the obtained identification information. For example, if communication between the LFA device 104 and the wireless chip 114 is encrypted and the wireless chip 114 does not know the encryption protocol, the LFA device 104 cannot read the identification information. In this scenario, the result determiner 602 determines that the LFA device 104 is invalid or unauthorized.

[0111] Once the result determiner 602 determines the flag and / or binary value corresponding to each test and / or control, the example result determiner 602 determines whether the test is ready by comparing the control results with the results corresponding to the complete test. For example, if the machine-readable LFA device 104, 300 has a positive control zone, the test is ready to be read when the positive control zone corresponds to a positive test result. If the example result determiner 602 determines that the value and / or flag corresponding to the positive control zone is not positive, the result determiner 602 determines that the test is not ready to be read, and the example component interface 600 outputs an error message or other informative message to the user via the user interface 120.

[0112] 6 determines that the tests are ready to be read, the result determiner 602 determines which tests resulted in a positive result and / or a negative result based on corresponding values ​​and / or flags in the received results. The example result determiner 602 instructs the component interface 600 to display the results to the user via the example user interface 120. Additionally, the result determiner 602 can store the results in the example result storage 606. The result determiner 602 can store the results along with the received identification information and / or any context or supplemental information (e.g., patient information, timestamp, demographics, location information, lot number, use by date, expiration date, test information, signal quality information, chain of custody, operator information, etc.).

[0113] 6 stores information corresponding to the number(s) and / or type(s) of tests and the number(s) and / or type(s) of controls, along with identification information (e.g., device identification, test structure identification, etc.) In this manner, once the identification information of the example LFA device 104, 300 is obtained, the example result determiner 602 can identify how the results correspond to different controls and / or tests.

[0114] 6 stores the results of the LFA tests (e.g., which tests presented a positive, negative, or indeterminate result, and / or any corresponding information), along with any identifying information (e.g., a data matrix code, test identifier, etc.). In some examples, a user may enter patient information via user interface 120. In those examples, some or all of the patient information may be added to the result information (e.g., result storage 606 stores a record of the test results along with the patient information). Additionally or alternatively, example component interface 600 may collect contextual information (e.g., location information, time information, etc.) when a test is performed, which may be stored in example result storage 606 along with the results.

[0115] The example timer / counter 608 of FIG. 6 tracks one or more durations (e.g., periods) to determine whether to tag a test as invalid or potentially invalid. For example, a test may be invalidated if a user performs an action after a predetermined duration has elapsed. For example, after a user verifies that sample and / or buffer have been applied, the example timer / counter 608 tracks a first duration corresponding to the time the test is ready to be read. Additionally, the timer / counter 608 can track a second duration corresponding to the time the user rescans the LFA device 104 to verify that it is the correct LFA device to be read. Additionally, the timer / counter 608 can track a third duration corresponding to the time the user stops the flow rate. The duration(s) may be based on a test algorithm corresponding to the type of test and / or the type of LFA device. In some examples, the timer / counter 608 outputs a timing window (e.g., a clock and / or countdown corresponding to one or more periods) to the user via the user interface 120.

[0116] An exemplary method for implementing the exemplary machine-readable LFA generator 102 of FIG. 1A is shown in FIG. 4, an exemplary method for implementing the exemplary wireless chip 114 of FIGS. 1A, 2A, 2B, 2G, 2I-2K and / or 3A is shown in FIG. 5, an exemplary method for implementing the exemplary machine-readable LFA reader application 117 of FIG. 1A is shown in FIG. 6, and one or more of the elements, processes and / or devices shown in FIGS. 4-6 may be combined, divided, rearranged, omitted, removed and / or implemented in any other manner. Additionally, the example user interface 400, example portion generator 402, example portion applicator 404, example antenna interface 500, example driver 502, example sensor 504, example comparator 506, example result storage 508, example component interface 600, example result determiner 602, example test type storage 604, example result storage 606, and / or more generally the example machine-readable LFA generator 102, example wireless chip 114, and / or example machine-readable LFA reader application 117 of FIGS. 4-6 may be implemented by hardware, software, firmware, and / or any combination of hardware, software, and / or firmware.Thus, for example, any of the example user interface 400, example portion generator 402, example portion applicator 404, example antenna interface 500, example driver 502, example sensor 504, example comparator 506, example result storage 508, example component interface 600, example result determiner 602, example test type storage 604, example result storage 606, and / or more generally, the example machine-readable LFA generator 102, example wireless chip 114, and / or example machine-readable LFA reader application 117 of FIGS. 4-6 may include one or more analog or digital circuit(s), logic circuit(s), programmable processor(s), programmable controller(s), graphics processing unit(s) (GPU(s)), digital signal processor(s), The present invention may be implemented by application specific integrated circuit(s) (DSP(s)), application specific integrated circuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)), and / or field programmable logic device(s) (FPLD(s)). If any of the apparatus or system claims of this patent are read as being intended to cover a purely software and / or firmware implementation, then at least one of the example user interface 400, example portion generator 402, example portion applicator 404, example antenna interface 500, example driver 502, example sensor 504, example comparator 506, example result storage 508, example component interface 600, example result determiner 602, example test type storage 604, example result storage 606, and / or more generally, the example machine-readable LFA generator 102, example wireless chip 114, and / or example machine-readable LFA reader application 117 of FIGS. 4-6 are expressly defined herein to include a non-transitory computer-readable storage device or storage disk, such as a memory, a digital versatile disc (DVD), a compact disc (CD), a Blu-ray disc, or the like, that contains software and / or firmware.4, the example wireless chip 114 of FIG. 5, and the example machine-readable LFA reader application 117 of FIG. 6 may include one or more elements, processes, and / or devices in addition to or instead of those shown in FIGs. 4-6, and / or may include more than one of any or all of the illustrated elements, processes, and devices. As used herein, the term "in communication," including variations thereof, encompasses direct communication and / or indirect communication via one or more intermediate components, and further includes selective communication at regular intervals, scheduled intervals, aperiodic intervals, and / or one-time events that do not require direct physical (e.g., wired) communication and / or constant communication, but rather

[0117] Flowcharts representing example hardware logic, machine-readable instructions, hardware-implemented state machines, and / or any combination thereof for implementing the machine-readable LFA generator 102, example wireless chip 114, and / or machine-readable LFA reader application 117 of Figures 4-6 are shown in Figures 7-11B. The machine-readable instructions may be one or more executable programs or portions of an executable program for execution by a computer processor, such as processors 1212, 1312, 1412 shown in example processor platforms 1200, 1300, 1410 described below in connection with Figures 12, 13, and / or 14. These programs may be embodied in software stored on a non-transitory computer-readable storage medium, such as a CD-ROM, floppy disk, hard drive, DVD, Blu-ray disk, or memory associated with processor 1212, 1312, 1412; alternatively, the entire program and / or portions thereof may be executed by devices other than processor 1212, 1312, 1412 and / or may be embodied in firmware or dedicated hardware. Furthermore, although example programs are described with reference to the flowcharts shown in FIGS. 7-11B, many other ways of implementing the example machine-readable LFA generator 102, the example wireless chip 114, and / or the example machine-readable LFA reader application 117 can alternatively be used. For example, the order of execution of the blocks may be changed, and / or some of the described blocks may be changed, eliminated, or combined. Additionally or alternatively, any or all of the blocks may be implemented by one or more hardware circuits (e.g., discrete and / or integrated analog and / or digital circuits, FPGAs, ASICs, comparators, operational amplifiers (op-amps), logic circuits, etc.) structured to perform the corresponding operations without executing software or firmware.

[0118] The machine-readable instructions described herein may be stored in one or more of a compressed format, an encrypted format, a fragmented format, a compiled format, an executable format, a packaged format, etc. The machine-readable instructions described herein may be stored as data (e.g., portions of instructions, code, representations of code, etc.) that can be utilized to create, manufacture, and / or generate machine-executable instructions. For example, the machine-readable instructions may be fragmented and stored on one or more storage devices and / or computing devices (e.g., servers). The machine-readable instructions may require one or more of installing, modifying, adapting, updating, combining, supplementing, configuring, decrypting, decompressing, decompressing, distributing, reassigning, compiling, etc. to make them directly readable, interpretable, and / or executable by the computing device and / or other machines. For example, the machine-readable instructions may be stored in multiple portions that are individually compressed, encrypted, and stored on separate computing devices, which, when decrypted, decompressed, and combined, form an executable instruction set that implements a program, such as those described herein.

[0119] In another example, the machine-readable instructions may be stored in a state that can be read by a computer, but may require the addition of a library (e.g., a dynamic link library (DLL)), a software development kit (SDK), an application programming interface (API), etc., to execute the instructions on a particular computing device or other device. In another example, the machine-readable instructions (e.g., storing settings, entering data, recording network addresses, etc.) may need to be configured before the machine-readable instructions and / or corresponding program(s) can be executed in whole or in part. Thus, disclosed machine-readable instructions and / or corresponding program(s) are intended to encompass such machine-readable instructions and / or program(s) regardless of the particular format or state of the machine-readable instructions and / or program(s) when stored or otherwise stationary or temporary.

[0120] The machine-readable instructions described herein may be expressed in any past, present, or future command language, scripting language, programming language, etc. For example, the machine-readable instructions may be expressed using any of the following languages: C, C++, Java, C#, Perl, Python, JavaScript, Hypertext Markup Language (HTML), Structured Query Language (SQL), Swift, etc.

[0121] 7-11B may be implemented using executable instructions (e.g., computer- and / or machine-readable instructions) stored on a non-transitory computer- and / or machine-readable medium, such as a hard disk drive, flash memory, read-only memory, compact disk, digital versatile disk, cache, random access memory, and / or any other storage device or storage disk on which information is stored for any duration (e.g., long-term, permanently, for brief instances, during temporary buffering, and / or during caching of information). As used herein, the term "non-transitory computer-readable medium" is expressly defined to include any type of computer-readable storage device and / or storage disk, to exclude propagating signals, and to exclude transmission media.

[0122] 7 shows an example flowchart representing machine-readable instructions 700 that may be executed to implement the example machine-readable LFA generator 102 of FIG. 4 to generate one of the example machine-readable LFA devices 104, 300 of FIG. 1A, 1B, 2A, 2B, 2D, 2E, 2H, 2L-2R, and / or 3A. Although the instructions 700 of FIG. 7 are described in connection with one of the example machine-readable LFA devices 104, 300 of FIG. 1A, 1B, 2A, 2B, 2D, 2E, 2H, 2L-2R, and / or 3A, the example instructions 700 may be written and / or implemented in combination with any type of LFA device of any configuration.

[0123] In block 702, the example user interface 400 determines whether instructions have been obtained to generate the machine-readable LFA device 104, 300. If the example user interface 400 determines that instructions have not been obtained (block 702: No), control returns to block 702 until instructions have been obtained. If the example user interface 400 determines that instructions have been obtained (block 702: Yes), the example portion generator 402 determines the number of tests, the type(s) of test(s), the number of control zones, and / or the type(s) of control zone(s) based on the user instructions (block 704). For example, a user can provide instructions to generate the LFA device 104, 300 to include three test zones corresponding to three target analytes and one positive control zone.

[0124] In block 706, the example portion generator 402 designs and / or retrieves a conjugate pad based on the type(s) of test(s) and / or LFA structure identified in the instructions. For example, the portion generator 402 may generate (and / or retrieve from storage) a conjugate pad including antibodies and / or antigens that attach to target analytes corresponding to the type(s) of test(s) identified in the instructions. In the case of the bioelectrochemical cell LFA device 104, the antigens and / or antibodies are attached to either GOx or gold nanoparticles (e.g., depending on how the bioelectrochemical cells 111a-n are structured). In the case of the circuit-complete LFA device 300, the antigens and / or antibodies are attached to gold nanoparticles.

[0125] In block 708, the example portion generator 402 generates and / or acquires the example sample pad 106, the example porous medium 109, the example absorbent pad 112, the example wireless chip 114, the example antenna 115, and / or the LFA housing. In block 710, the example portion applicator 404 applies (e.g., immobilizes) antigens and / or antibodies corresponding to the target analytes and / or accesses the target analytes to test zones and / or control zones within the test area 110 of the porous medium 109. In block 712, the example portion generator 402 determines whether the instructions correspond to an LFA that is a bioelectrochemical cell LFA device 104 (e.g., rather than a circuit-complete LFA device 300). If the portion generator 402 determines that the LFA does not correspond to a bioelectrochemical cell LFA device 104 (block 712: No), control continues to block 716. If the portion generator 402 determines that the LFA corresponds to a bioelectrochemical cell LFA device 104 (block 712: Yes), the example portion generator 402 generates and / or acquires a bioelectrochemical cell (block 714). The example portion generator 402 generates the bioelectrochemical cell by impregnating a paper strip or other substance with an enzyme substrate (e.g., glucose) and / or a reducing agent (e.g., hydroquinone, aminophenol, vitamin C, other ascorbic acid, etc.), and / or an electron mediator or redox species (e.g., potassium ferricyanide, ferrocene, ferrocene derivatives, etc.). Once impregnated, the example portion generator 402 dries the bioelectrochemical cell before applying it to the LFA device 104.

[0126] In block 716, the exemplary portion applicator 404 generates (e.g., assembles and / or applies) one of the machine-readable LFAs 104, 300, including the sample pad 106, the exemplary conjugate pad 108, the exemplary porous medium 109, the exemplary absorbent pad 112, the exemplary wireless chip 114, the exemplary antenna 115, wiring or etchings (e.g., for connecting the wireless chip 114 to the test zone and / or cell), electrodes 202a-f, switch 278, flow arrester 280, electrode substrate 282, actuator 293, and / or LFA housing. In block 718, the exemplary portion applicator 404 applies the exemplary inlet 113 (e.g., by cutting away a portion of the LFA device 104, 300). In some examples, the inlet may not be included. For example, in the case of the circuit-complete LFA device 300, the silver amplification material can be applied to the exemplary sample pad 106 and flow through the exemplary lines 302, 304, 306.

[0127] FIG. 8A shows an example flowchart representing machine-readable instructions 800 that may be executed to implement the example wireless chip 114 of FIG. 5 to determine results of a test from the example bioelectrochemical cell LFA device 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R. However, the instructions 800 of FIG. 8A are described in conjunction with one of the example machine-readable LFA devices 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R. The example instructions 800 may be described and / or implemented in conjunction with any type of LFA device of any configuration. The example instructions 800 may be described and / or implemented in conjunction with any type of LFA device of any configuration, including, for example, the LFA device of FIGS. 3A and 3B.

[0128] In block 802, the example antenna interface 500 obtains power via the antenna 115. For example, the example reader 116 generates a local electromagnetic field that induces a current in the example antenna 115 to power the example wireless chip 114. In block 804, the example sensor 504 senses the voltage drop and / or current flow between corresponding pins coupled to the test and / or control zones via the example electrodes 308 a, 308 b. The example sensor 504 can sense the voltage drop and / or current flow of each zone in series or in parallel.

[0129] In block 806, the example comparator 506 determines whether the voltage drop and / or current flow exceeds a threshold value for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed voltage drop and / or current flow for each test and / or control exceeds 50 mV. In some examples, the comparator 506 determines whether the voltage drop and / or current flow exceeds multiple different threshold values. In this manner, the comparator 506 can determine how much the sensed voltage drop and / or current flow was, as described above in connection with FIGS. 2A-2K. If the example comparator 506 determines that the voltage drop and / or current flow did not exceed a threshold value for one or more corresponding pins (block 806: No), control continues to block 810. If the example comparator 506 determines that the voltage drop and / or current flow exceeds the threshold for one or more corresponding pins (block 806: YES), the example comparator 506 flags (e.g., marks or outputs a logical value) the corresponding test zone(s) and / or control zone(s) as corresponding to a positive result (block 808). The example result storage 508 stores the flag(s) along with the corresponding zone(s), as further disclosed below in block 814.

[0130] In block 810, the example comparator 506 determines whether the voltage drop and / or current flow is below a threshold value for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed voltage drop and / or current flow for each test and / or control is below 50 mV. If the example comparator 506 determines that the voltage drop and / or current flow is not below a threshold value for one or more corresponding pins (block 810: no), control continues to block 814. If the example comparator 506 determines that the voltage drop and / or current flow is below a threshold value for one or more corresponding pins (block 810: yes), the example comparator 506 flags (e.g., marks or outputs a logic value) the corresponding test zone(s) and / or control zone(s) as corresponding to a negative result (block 812). At block 814, the example results storage 508 stores the flag(s) with the corresponding zone(s), and / or the example antenna interface 500 transmits (e.g., via antenna 115) the results corresponding to the flags. The antenna 115 may also transmit identifying information (e.g., a device identifier, an identifier for the number and / or type of test, an identifier for the number and / or type of control) along with the results.

[0131] FIG. 8B shows an example flowchart representing alternative machine-readable instructions 820 that may be executed to implement the example wireless chip 114 of FIG. 5 to determine results of tests from the example bioelectrochemical cell LFA devices 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R. However, the instructions 820 of FIG. 8B are described in conjunction with one of the example machine-readable LFA devices 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R. The example instructions 820 may be described and / or implemented in conjunction with any type of LFA device of any configuration. The example instructions 800 may be described and / or implemented in conjunction with any type of LFA device of any configuration, including, for example, the LFA devices of FIGS. 3A and 3B.

[0132] At block 822, the example antenna interface 500 obtains power via the antenna 115. For example, the example reader 116 generates a local electromagnetic field that induces a current in the example antenna 115 to power the example wireless chip 114. At block 824, the example driver toggles between electrode pairs to enable the sensor 504 to obtain one or more voltage and / or current samples between corresponding pins coupled to the test and / or control zones. For example, the driver 502 can toggle a select line of one of the example front ends 240, 250 to enable the sensor 504 to sense the voltage drop and / or current flow between the corresponding electrodes. As described above, the driver 502 can control the front ends 240, 250 to obtain multiple samples of each test and / or control line. In some examples, the sensor 504 may obtain voltage / current directly from a channel of the front end 260 without toggling. Additionally or alternatively, the example LFA device 104 can obtain any data corresponding to the test results. At block 826, the example analog-to-digital converter 512 converts the analog voltage and / or current measurements to digital value(s). At block 828, the example antenna interface 500 transmits the digital voltage values ​​of the zones along with corresponding information (e.g., device identifier, test type identifier, product code, etc.) to the reader 116 (e.g., via the antenna 115). In some examples, block 826 may be omitted and the example antenna interface 500 may transmit the analog voltage and / or current measurements to the example reader 116. In some examples, the wireless chip 114 may compare the measurements to one or more thresholds to generate a result, as further described above in connection with FIG. 8A .

[0133] 9 shows an example flowchart representing machine-readable instructions 900 that may be executed to implement the example wireless chip 114 of FIG. 5 to determine the results of a test from the example bioelectrochemical cell LFA device 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R that is powered from a voltage generated by one or more of the bioelectrochemical cells 111a-111n. Although the instructions 900 of FIG. 9 are described in connection with one of the example machine-readable LFA devices 104 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, and / or 2L-2R, the example instructions 900 may be written and / or implemented in combination with any type of LFA device of any configuration.

[0134] In block 902, the exemplary wireless chip 114 obtains power from one or more of the bioelectrochemical cells 111 a-n. As described above, when one or more of the test zones and / or control zones immobilize a target analyte, a voltage is generated in one or more of the bioelectrochemical cells 111 a-n. The generated voltage can be used to power the wireless chip 114. In block 904, the exemplary timer 510 starts a wait timer. When the wait timer reaches a time threshold (e.g., an assay time), the test is ready to be read. In this way, if the reader 116 attempts to read the LFA 104 before it is ready to be read, the wireless chip 114 can transmit the wait time and / or assay time so that the reader 116 can display the time remaining until the LFA 104 is ready to be read.

[0135] In block 906, the example antenna interface 500 determines whether an electromagnetic field is sensed via the example antenna 115. When the reader 116 attempts to read the LFA 104, the reader 116 generates an electromagnetic field and initiates communication with the wireless chip 114. If the example antenna interface 500 determines that an electromagnetic field is not sensed (block 906: no), control returns until an electromagnetic field is sensed. If the example antenna interface 500 determines that an electromagnetic field is sensed (block 906: yes), the comparator 506 determines whether the wait time (e.g., from the example timer 510) exceeds the assay time (e.g., a threshold time corresponding to the test being ready to read) (block 908). If the example comparator 506 determines that the wait time does not exceed the assay time (block 908: no), the example antenna interface 500 interfaces with the antenna 115 to transmit timing information (e.g., the current wait time and / or assay time) to the example reader 116 (block 910). In this way, the reader 116 can determine how much more time is needed and / or display the time to the user. Reading the results too early and / or erroneously reading other results is prevented because the process 900 includes determining whether the wait time exceeds the assay time.

[0136] If the example comparator 506 determines that the wait time exceeds the assay time (block 908: yes), the example sensor 504 senses a voltage drop across the corresponding pins coupled to the test and / or control zones via the example electrodes 308a, 308b (block 914). The example sensor 504 can sense the voltage drop across each zone in series or in parallel. In block 916, the example comparator 506 determines whether the voltage drop exceeds a threshold value for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed voltage drop across each test and / or control exceeds 50 mV. If the example comparator 506 determines that the voltage drop does not exceed a threshold value for one or more corresponding pins (block 916: no), control continues to block 920. If the example comparator 506 determines that the voltage drop exceeds the threshold for one or more corresponding pins (block 916: YES), the example comparator 506 flags (e.g., marks or outputs a logical value) the corresponding test zone(s) and / or control zone(s) as corresponding to a positive result (block 918). The example result storage 508 stores the flag(s) along with the corresponding zone(s), as further disclosed below in block 924.

[0137] In block 920, the example comparator 506 determines whether the voltage drop is below a threshold value for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed voltage drop for each or each of the test and / or control is below 50 mV. If the example comparator 506 determines that the voltage drop is not below a threshold value for one or more corresponding pins (block 920: no), control continues to block 924. If the example comparator 506 determines that the voltage drop is below a threshold value for one or more corresponding pins (block 920: yes), the example comparator 506 flags (e.g., marks or outputs a logical value) the corresponding test zone(s) and / or control zone(s) as corresponding to a negative result (block 922). In block 924, the example result storage 508 stores the flag(s) with the corresponding zone(s), and / or the example antenna interface 500 transmits (e.g., via antenna 115) a result corresponding to the flag. Antenna 115 may also transmit identifying information (eg, a device identifier, an identifier for the number and / or type of test, an identifier for the number and / or type of control) along with the results.

[0138] 10 shows an example flowchart representing machine-readable instructions 1000 that may be executed to implement the example wireless chip 114 of FIG. 5 to determine the results of a test from the example circuit-complete LFA device 300 of FIG. 3A. Although the instructions 1000 of FIG. 10 are described in connection with the example machine-readable LFA device 300 of FIG. 3A, the example instructions 1000 may be written and / or implemented in conjunction with any type of LFA device of any configuration.

[0139] In block 1002, the example antenna interface 500 obtains power via the antenna 115. For example, the example reader 116 generates a local electromagnetic field that induces a current in the example antenna 115 and powers the example wireless chip 114. In block 1004, the example driver 502 outputs a voltage to a first pin coupled to the first electrode 308a of the test zone(s) and / or control zone(s). The example driver 502 can output a voltage to each of the first pins in parallel or series. In block 1006, the example sensor 504 senses a current and / or resistance from a second pin coupled to the second electrode 308b of the test zone(s) and / or control zone(s).

[0140] In block 1008, the example comparator 506 determines whether the current exceeds a threshold value or whether the resistance is below a threshold value for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed current for each test and / or control is within a predetermined range. In some examples, the comparator 506 determines whether the current / resistance exceeds multiple different threshold values. In this manner, the comparator 506 can determine what the sensed current / resistance was, as described above in connection with FIGS. 2A-2K. If the example comparator 506 determines that the current does not exceed a threshold value or the resistance does not fall below a threshold value for one or more corresponding pins (block 1008: No), control continues to block 1012. If the example comparator 506 determines that the current exceeds a threshold or the resistance falls below a threshold for one or more corresponding pins (block 1008: yes), the example comparator 506 flags (e.g., marks or outputs a logical value) the corresponding test zone(s) and / or control zone(s) as corresponding to a positive result (block 1010). The example result storage 508 stores the flag(s) along with the corresponding zone(s), as further disclosed below in block 1016.

[0141] In block 1012, the example comparator 506 determines whether the current is below a threshold or whether the resistance is above a threshold for one or more corresponding pins. For example, the comparator 506 may determine whether the sensed current for each test and / or control is within a predetermined range of current and / or resistance. In other examples, the comparator 506 performs a comparison metric against specific values. For example, in an example implementation, the comparator 506 may determine whether the sensed current for a test and / or control is below 50 mA and / or whether the sensed resistance is above 100 ohms. In other examples, other values ​​may be used. If the example comparator 506 determines that the current is not below a threshold or the resistance is not above a threshold for one or more corresponding pins (block 1012: No), control continues to block 1016. If the example comparator 506 determines that the current is below a threshold or the resistance is above a threshold for one or more corresponding pins (block 1012: yes), the example comparator 506 flags (e.g., marks or outputs a logical value) the corresponding test zone(s) and / or control zone(s) as corresponding to a negative result (block 1014). In block 1016, the example result storage 508 stores the flag(s) with the corresponding zone(s), and / or the example antenna interface 500 transmits (e.g., via the antenna 115) the results corresponding to the flag(s). The antenna 115 may also transmit identifying information (e.g., a device identifier, an identifier for the number and / or type of test, an identifier for the number and / or type of control) with the results. In some examples, the result storage 606 can store a flag indicating that a result has been determined. The flag may be included in the results of subsequent reads. In this manner, the example reader 116 can identify that a test has already been read.

[0142] 11A-11B show an example flowchart representing machine-readable instructions 1100 that may be executed to implement the example machine-readable LFA reader application 117 of FIG. 6 to read test results (e.g., diagnostic test results) of the example machine-readable LFA devices 104, 300 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, 2L-2R, and / or 3A. Although the instructions 1100 of FIGS. 11A-11B are described in connection with the example machine-readable LFA devices 104, 300 of FIGS. 1A, 1B, 2A, 2B, 2D, 2E, 2G, 2H, 2L-2R, and / or 3A, the example instructions 1100 may be written and / or implemented in combination with any type of LFA configuration.

[0143] The result determiner 602 instructs the component interface 600 to interface with the user of the reader 116 via the user interface 120. The result determiner 602 can send one or more prompts to the user and wait for an affirmative response from the user. For example, if the test of the LFA 104 is not autonomous or semi-autonomous, the result determiner 602 can send instructions to the user of the reader 116 when the application 117 launches on the reader 116. For example, in block 1102, the example result determiner 602 outputs a prompt to the user of the reader 116 instructing the user to enter characteristic information (e.g., name, age, date of birth, gender, etc.). For example, the result determiner 602 instructs the component interface 600 to interface with the user via the user interface 120. The result determiner 602 can send one or more prompts to the user and wait for an affirmative response from the user. The patient information may be included in corresponding information that may be displayed, stored, and / or transmitted to an external database and / or server (e.g., tagged with the results, included as metadata for the results, etc.). In some examples, the external / remote database and / or server may be located at or otherwise associated with an EMR, government agency, NGO, doctor's office, hospital, hospital information system, LIMS system, inventory consumption monitor, clinic, and / or other healthcare facility, medical device manufacturer, healthcare organization, healthcare information system, and / or other external entity.

[0144] The result determiner 602 also sends a prompt to the user to register the LFA 104 and / or to identify the type of LFA 104. In block 1104, the result determiner 602 commands the example antenna 118 via the example component interface 600 to generate a magnetic field and power the wireless chip 114 for a first scan (e.g., to identify the LFA device 104). In this manner, the wireless chip 114 can provide information to the reader 116 (e.g., wirelessly via the example antenna 115) while powered. In some examples, the reader 104 can obtain the identification information by using a camera to scan a QR code on the LFA device 104 or by having the user manually enter a code on the LFA device 104. The LFA reader application 117 presents instructions to the user to scan the LFA device 104 (e.g., bring the reader 116, operating with the reader application 117, close to the LFA device 104). In block 1106, the example result determiner 602 obtains a test identifier (e.g., corresponding to one or more tests the LFA device is configured to undergo), an LFA device identifier, a product code, and / or any other encoded or non-encoded data from the wireless chip 114. The obtained information may be included in corresponding information (e.g., tagged with the results, included as metadata for the results, etc.) that can be displayed, stored, and / or transmitted to an external database and / or server. In some examples, the result determiner 602 uses the obtained information to determine a test type and / or corresponding algorithm to use when obtaining data corresponding to the test results from the LFA device 104. In some examples, the result determiner 602 uses the obtained information to authenticate the LFA device 104 and / or disable use of an invalid or unauthorized LFA device 104.

[0145] At block 1108, the example result determiner 602 determines the geographic location of the LFA device 104. In some examples, the component interface 600 accesses location information from other components of the reader 116 (e.g., if the reader 116 includes a GPS system). In some examples, the geographic location information is received (e.g., accessed, obtained, etc.) from the wireless chip 114. The geographic location information may be included in corresponding information (e.g., tagged with the results, included as metadata for the results, etc.), which may be displayed, stored, and / or transmitted to an external database and / or server.

[0146] In block 1110, the example result determinator 602 guides the user of the reader 116 through the LFA reading instructions. For example, the result determinator 602 can transmit instructions such as: (1) instructions to instruct the user to apply sample to the sample pad 106 and wait for the user's affirmative response; (2) instructions to instruct the user to apply assay buffer and wait for the user's affirmative response; (3) instructions to instruct the user to wait for the LFA test, display the time, and / or wait for the user's affirmative response; (4) instructions to instruct the user to apply reaction buffer and wait for the user's affirmative response; (5) instructions to instruct the user to wait for the reaction to occur, display the time, and / or wait for the user's affirmative response. In some examples, the result determinator 602 can indicate an error, for example, if an affirmative response is not received within a threshold range of time. In semi-autonomous or fully autonomous LFAs, some instructions may be omitted because the LFA 104 can perform one or more steps automatically without the need for a user. The added information may be included in corresponding information that may be displayed, stored, and / or transmitted to an external database and / or server (e.g., tagged with the results, included as metadata for the results, etc.). In some examples, the external database and / or server is a hospital, a hospital information system, a LIMS system, an inventory consumption monitor, a medical facility, a medical device manufacturer, etc.

[0147] In block 1112, the example component interface 600 determines whether the user verified that sample and / or buffer was applied to the example LFA 104 (e.g., by an affirmative response on the user interface 120). If the example component interface 600 determines that the user did not verify that sample and / or buffer was applied (block 1112: no), control returns to block 1112 until the user does. If the example component interface 600 determines that the user verified that sample and / or buffer was applied (block 1112: yes), the example result determiner 602 determines whether the flow rate needs to be stopped (block 1114). In some examples, the result determiner 602 determines whether the flow rate needs to be stopped by tracking a time window, where the time window is based on test and / or LFA identification information. For example, the LFA device 104 of Figures 2A-2E and / or 2L-2R uses techniques such as shearing, cutting, compression, etc. to reduce or prevent flow over the porous membrane 109, preventing the product (e.g., hydrogen peroxide) generated at the test or control line from flowing toward the absorbent pad 112.

[0148] If the example component interface 600 determines that the flow rate does not need to be stopped (block 1114: no), control proceeds to block 1114 until the time window expires. If the example component interface 600 determines that the flow rate along the LFA device 104 needs to be stopped (block 1114: yes), the example component interface 600 instructs the user to scan the LFA device 104 (block 1116). Because a user may be running multiple tests from multiple LFA devices simultaneously within a short duration, the user may become confused about which test is ready to be read. Therefore, the LFA reader application 117 prevents errors associated with running multiple tests simultaneously and / or within a short duration by instructing the user to scan the LFA device 104 to verify that the device the user scanned is the correct device to drive.

[0149] In block 1118, the result determiner 602 commands the example antenna 118 via the example component interface 600 to generate a magnetic field, power the wireless chip 114, and perform a second scan (e.g., to validate that the user is reading the correct LFA device 104). In block 1120, the example result determiner 602 determines whether the identification of the LFA device is verified (e.g., whether the identification of the first scan matches the identification of the second scan). If the example result determiner 602 determines that the identification of the LFA device is verified (block 1120: yes), control continues to block 1126 of FIG. 11B. If the example result determiner 602 determines that the identity of the LFA device is not verified (e.g., the identifier from the second scan does not match the identifier from the first scan) (block 1120: NO), the example result determiner 602 determines whether the scan window has ended (e.g., the time corresponding to the time the LFA device 104 needs to be verified has ended based on the test and / or LFA device type) (block 1122). If the scan window has ended, the accuracy of the results may be reduced. In some examples, the component interface 600 displays a timer corresponding to the test window within the example user interface 120.

[0150] If the example result determiner 602 determines that the scan window has not ended (block 1122: no), control returns to block 1116. If the example result determiner 602 determines that the scan window has ended (block 1122: yes), the example result determiner 602 flags the test as potentially invalid (block 1124), and control returns to block 1116. In some examples, the test may continue, but the results are read after the scan window and then flagged (e.g., along with timing information corresponding to the time from the end of the scan window until the results are determined). In some examples, the test is marked invalid, and the component interface 600 identifies the test as invalid.

[0151] In block 1126, the example component interface 600 sends a prompt to the user to stop the flow of the LFA device 104 (block 1114). For example, the component interface 600 can prompt the user to move the switches 278, 292 from the first position to the second position, which can cause the flow arrestor 280 to cut, shear, compress, and / or otherwise stop, slow, and / or resist the flow of fluid. In block 1128, the result determiner 602 determines (e.g., via a prompt on the user interface 120) whether the user verified that the flow of fluid has stopped. If the example result determiner 602 determines that the user verified that the flow of fluid has stopped (block 1128: yes), control continues to block 1134. If the example result determiner 602 determines that the user has not verified that the flow rate has stopped (block 1128: NO), the example result determiner 602 determines whether the flow rate stop window has ended (e.g., whether the time corresponding to the time the LFA device 104 needs to be sheared has ended based on the type of test and / or LFA device) (block 1130). If the flow rate stop window has ended, the accuracy of the results may be reduced. In some examples, the component interface 600 displays a timer corresponding to the test window within the example user interface 120.

[0152] If the example result determiner 602 determines that the flow stop window has not ended (block 1130: no), control returns to block 1126. If the example result determiner 602 determines that the scan window has ended (block 1130: yes), the example result determiner 602 flags the test as potentially invalid (block 1132), and control returns to block 1126. In some examples, the test may continue, but the results are read after the flow stop window and then flagged (e.g., along with timing information corresponding to the time from the end of the flow stop window until the results are determined). In some examples, the test is marked as invalid, and the component interface 600 identifies the test as invalid.

[0153] At block 1134, the example component interface 600 instructs the user to scan the LFA device 104. At block 1136, the result determiner 602 instructs the example antenna 118 via the example component interface 600 to generate a magnetic field, power the wireless chip 114, and perform a third scan (e.g., to obtain digital values ​​from the LFA device 104). As described above, the digital values ​​may correspond to sensed voltage(s) and / or current(s) from one or more test zones and / or control zones. At block 1138, the example result determiner 602 processes results based on the obtained test data (e.g., digital voltage and / or current values ​​tagged to the test zones and / or control zones) and an algorithm corresponding to the LFA identifier. Because the machine-readable LFA reader application 117 can scan different LFA devices and the algorithms for determining and / or categorizing results based on the acquired data can differ for different devices and / or different diagnostic tests, the LFA reader application 117 determines an algorithm to apply based on the test identifier from the LFA device 104 and determines a test result using the acquired test data and the selected algorithm. The algorithm can define thresholds that identify voltage and / or current values ​​that result in a positive result and voltage and / or current values ​​that result in a negative result. Further, the algorithm can determine how many samples must be positive to result in a positive result (e.g., 5 out of 5 (i.e., all), 4 out of 5 (i.e., a percentage), etc.). In some examples, the wireless chip 114 determines the test result itself. In such examples, the result determiner 602 may display and / or store the results obtained based on the corresponding algorithm. In this manner, the outcome determination 602 associated manufacturing data encoded on the wireless chip 114 (eg, the ASIC of the wireless chip 114) with test results without connecting to a secondary system.

[0154] In block 1140, the example result determiner 602 determines whether the results need to be displayed on the example user interface 120. For example, for privacy reasons, a patient may want the results sent to their doctor rather than displayed to a technician. Thus, to protect the patient's privacy, a setting may be enabled or disabled corresponding to displaying or not displaying the results. If the example result determiner 602 determines that the results do not need to be displayed (e.g., kept private from the user administering the test) (block 1140: no), control continues to block 1144. If the example result determiner 602 determines that the results need to be displayed (block 1140: yes), the example component interface 600 instructs the user interface 120 to display the results (block 1142). In block 1144, the example results storage 606 stores the results, corresponding information (e.g., device and / or test identification information), and / or contextual information or supplemental information (e.g., time, date, patient information, location information, lot number, expiration date, expiration date, test information, signal quality information, chain of custody, operator information, etc.). In some examples, the results are tagged to the patient and the corresponding information and / or contextual data is tagged to the results as metadata. Thus, the test data can be immediately associated with the supplemental data set.

[0155] In block 1146, the example component interface 600 sends an instruction to the transmitter of the reader 116 to transmit the results, corresponding information (e.g., device and / or test identification information), and / or context or supplemental information (e.g., time, date, patient information, location information, lot number, use by date, expiration date, test information, signal quality information, chain of custody, operator information, etc.). The example component interface 600 may transmit the results, corresponding information, and / or context or supplemental information over a network to one or more remote databases and / or servers located at or otherwise associated with an EMR, government agency, NGO value proposition, examination room, hospital, hospital information system, LIMS system, inventory consumption monitor, clinic, and / or other healthcare facility, medical device manufacturer, healthcare organization, healthcare information system, and / or other external entity. In this manner, different actions can be performed based on receipt of the test data. For example, hospitals, doctors' offices, manufacturers, distributors, etc. can automatically track the use of LFA devices when they are scanned for reading, automatically reordering additional inventory from suppliers, generating alerts of disease or pathogen outbreaks in specific areas, etc. In some examples, results and / or other data are automatically uploaded. In some examples, results and / or other data are uploaded in real time or near real time. In some examples, the reader 116 encrypts the information for transmission to an external database and / or server. When the results and corresponding information are transmitted to a monitoring entity, the monitoring entity can process the results and / or perform statistical analysis to determine whether there is a disease outbreak, identify whether the LFA is counterfeit, etc. based on multiple results received from one or more improved LFA reader applications. In some examples, the result determiner 602 prevents duplicate results from being transmitted (e.g., if a device is flagged as being read more than once).If a network connection does not currently exist, the example component interface 600 may delay issuing instructions to the transmitter until a network connection is established. Additionally or alternatively, the example component interface 600 may transmit results from the results storage 606 periodically, irregularly, and / or based on a trigger (e.g., a result request from the measurement entity).

[0156] Figure 12 is a block diagram of an exemplary processor platform 1200 structured to execute the instructions of Figure 7 to implement the machine-readable LFA generator 102 of Figure 4. The processor platform 1200 can be, for example, a server, a personal computer, a workstation, a self-learning machine (e.g., neural network), an internet appliance, or any other type of computing device.

[0157] The processor platform 1200 of the illustrated example includes a processor 1212. The processor 1212 of the illustrated example is hardware. For example, the processor 1212 can be implemented by one or more integrated circuits, logic circuits, microprocessors, GPUs, DSPs, or controllers from any desired group or manufacturer. A hardware processor may be a semiconductor-based (e.g., silicon-based) device. In this example, the processor implements the example user interface 400, the example portion generator 402, and the example portion applicator 404.

[0158] The processor 1212 of the illustrated example includes local memory 1213 (e.g., cache). The processor 1212 of the illustrated example communicates with main memory, including volatile memory 1214 and non-volatile memory 1216, via bus 1218. The volatile memory 1214 may be implemented by synchronous dynamic random access memory (SDRAM), dynamic random access memory (DRAM), RAMBUS® dynamic random access memory (RDRAM®), and / or any other type of random access memory device. The non-volatile memory 1216 may be implemented by flash memory and / or any other desired type of memory device. Access to the main memory 1214, 1216 is controlled by a memory controller.

[0159] The processor platform 1200 of the illustrated example also includes an interface circuit 1220. The interface circuit 1220 may be implemented by any type of interface standard, such as an Ethernet interface, a Universal Serial Bus (USB), a Bluetooth® interface, a Near Field Communication (NFC) interface, and / or a PCI Express interface.

[0160] In the illustrated example, one or more input devices 1222 are connected to interface circuit 1220. Input device(s) 1222 allow a user to input data and / or commands into processor 1212. The input device(s) can be implemented by, for example, an audio sensor, a microphone, a camera (still or video), a keyboard, buttons, a mouse, a touchscreen, a trackpad, a trackball, an isopoint, and / or a voice recognition system.

[0161] One or more output devices 1224 are also connected to the interface circuit 1220 of the illustrated example. The output device(s) 1224 can be implemented by, for example, a display device (e.g., a light emitting diode (LED), an organic light emitting diode (OLED), a liquid crystal display (LCD), a cathode ray tube display (CRT), an in-place switching (IPS) display, a touch screen, etc.), a tactile output device, a printer, and / or a speaker. Accordingly, the interface circuit 1220 of the illustrated example typically includes a graphics driver card, a graphics driver chip, and / or a graphics driver processor.

[0162] The interface circuitry 1220 of the illustrated example also includes communications devices such as transmitters, receivers, transceivers, modems, residential gateways, wireless access points, and / or network interfaces to facilitate data exchange with external machines (e.g., computing devices of any type) over the network 1226. Communications can be via, for example, an Ethernet connection, a digital subscriber line (DSL) connection, a telephone line connection, a coaxial cable system, a satellite system, a line-of-sight wireless system, a cellular phone system, etc.

[0163] The processor platform 1200 of the illustrated example also includes one or more mass storage devices 1228 for storing software and / or data. Examples of such mass storage devices 1228 include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, redundant array of independent disks (RAID) systems, and digital versatile disk (DVD) drives.

[0164] The machine-executable instructions 1232 of FIG. 7 may be stored on the mass storage device 1228, the volatile memory 1214, the non-volatile memory 1216, and / or a removable, non-transitory computer-readable storage medium such as a CD or DVD.

[0165] Figure 13 is a block diagram of an exemplary processor platform 1300 structured to execute the instructions of Figures 8A-10 to implement the wireless chip 114 of Figure 5. The processor platform 1300 can be, for example, a machine-readable LFA device, a self-learning machine (e.g., a neural network), or any other type of computing device.

[0166] The processor platform 1300 of the illustrated example includes a processor 1312. The processor 1312 of the illustrated example is hardware. For example, the processor 1312 can be implemented by one or more integrated circuits, logic circuits, microprocessors, GPUs, DSPs, or controllers from any desired group or manufacturer. A hardware processor may be a semiconductor-based (e.g., silicon-based) device. In this example, the processor implements the example antenna interface 500, the example driver 502, the example sensor 504, and the example comparator 506.

[0167] The processor 1312 of the illustrated example includes a local memory 1313 (e.g., a cache). The processor 1312 of the illustrated example communicates with a main memory, including a volatile memory 1314 and a non-volatile memory 1316, via a bus 1318. The volatile memory 1314 may be implemented by SDRAM, DRAM, RDRAM, and / or any other type of random access memory device. The non-volatile memory 1316 may be implemented by flash memory and / or any other desired type of memory device. Access to the main memory 1314, 1316 is controlled by a memory controller. The exemplary local memory 1313 implements the result storage 508.

[0168] The processor platform 1300 of the illustrated example also includes an interface circuit 1320. The interface circuit 1320 may be implemented with any type of interface standard, such as an Ethernet interface, a USB, a Bluetooth® interface, an NFC interface, and / or a PCI Express interface.

[0169] In the illustrated example, one or more input devices 1322 are connected to the interface circuit 1320. The input device(s) 1322 allow a user to input data and / or commands into the processor 1312. The input device(s) may be implemented, for example, by audio sensors, buttons, and / or any other type of input device(s).

[0170] One or more output devices 1324 are also connected to the interface circuit 1320 of the illustrated example. The output device(s) 1324 may be implemented, for example, by a display device (e.g., an LED, OLED, LCD, CRT display, IPS display, touch screen, etc.) and / or a speaker. Accordingly, the interface circuit 1320 of the illustrated example typically includes a graphics driver card, a graphics driver chip, and / or a graphics driver processor.

[0171] The interface circuitry 1320 of the illustrated example also includes communication devices such as transmitters, receivers, transceivers, modems, residential gateways, wireless access points, and / or network interfaces to facilitate data exchange with external machines (e.g., computing devices of any type) over a network 1326. Communication can be via, for example, an Ethernet connection, a DSL connection, a telephone line connection, a coaxial cable system, a satellite system, a line-of-sight wireless system, a cellular phone system, etc.

[0172] The processor platform 1300 of the illustrated example also includes one or more mass storage devices 1328 for storing software and / or data. Examples of such mass storage devices 1328 include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, RAID systems, and DVD drives.

[0173] The machine-executable instructions 1332 of FIGS. 8A-10 may be stored on the mass storage device 1328, the volatile memory 1314, the non-volatile memory 1316, and / or a removable, non-transitory computer-readable storage medium such as a CD or DVD.

[0174] Figure 14 is a block diagram of an exemplary processor platform 1400 structured to execute the instructions of Figures 11A-B to implement the machine-readable LFA reader application 117 of Figure 3. The processor platform 1400 can be, for example, a personal computer, a workstation, a self-learning machine (e.g., neural network), a mobile device (e.g., a mobile phone, a smartphone, a tablet such as an iPad™), a personal digital assistant (PDA), a personal video recorder, or any other type of computing device.

[0175] The processor platform 1400 of the illustrated example includes a processor 1412. The processor 1412 of the illustrated example is hardware. For example, the processor 1412 can be implemented by one or more integrated circuits, logic circuits, microprocessors, GPUs, DSPs, or controllers from any desired group or manufacturer. A hardware processor may be a semiconductor-based (e.g., silicon-based) device. In this example, the processor implements the example component interface 600 and the example result determiner 602.

[0176] The processor 1412 of the illustrated example includes a local memory 1413 (e.g., a cache). The processor 1412 of the illustrated example communicates with a main memory, including a volatile memory 1414 and a non-volatile memory 1416, via a bus 1418. The volatile memory 1414 may be implemented by SDRAM, DRAM, RDRAM, and / or any other type of random access memory device. The non-volatile memory 1416 may be implemented by flash memory and / or any other desired type of memory device. Access to the main memories 1414, 1416 is controlled by a memory controller. The example local memory 1413 implements the example test type storage 604 and the example results storage 606.

[0177] The processor platform 1400 of the illustrated example also includes an interface circuit 1420. The interface circuit 1420 may be implemented with any type of interface standard, such as an Ethernet interface, a USB, a Bluetooth® interface, an NFC interface, and / or a PCI Express interface.

[0178] In the illustrated example, one or more input devices 1422 are coupled to the interface circuit 1420. The input device(s) 1422 allow a user to input data and / or commands into the processor 1412. The input device(s) can be implemented, for example, by an audio sensor, a microphone, a camera (still or video), a keyboard, buttons, a mouse, a touchscreen, a trackpad, a trackball, an isopoint, and / or a voice recognition system.

[0179] One or more output devices 1424 are also connected to the interface circuit 1420 of the illustrated example. The output device(s) 1424 can be implemented, for example, by a display device (e.g., an LED, OLED, LCD, CRT display, IPS display, touch screen, etc.), a tactile output device, a printer, and / or a speaker. Accordingly, the interface circuit 1420 of the illustrated example typically includes a graphics driver card, a graphics driver chip, and / or a graphics driver processor.

[0180] The interface circuitry 1420 of the illustrated example also includes communications devices such as transmitters, receivers, transceivers, modems, residential gateways, wireless access points, and / or network interfaces to facilitate data exchange with external machines (e.g., computing devices of any type) over a network 1426. Communications can be via, for example, an Ethernet connection, a DSL connection, a telephone line connection, a coaxial cable system, a satellite system, a line-of-sight wireless system, a cellular phone system, etc.

[0181] The processor platform 1400 of the illustrated example also includes one or more mass storage devices 1428 for storing software and / or data. Examples of such mass storage devices 1428 include floppy disk drives, hard drive disks, compact disk drives, Blu-ray disk drives, RAID systems, and DVD drives.

[0182] The machine-executable instructions 1432 of Figures 11A-B may be stored on the mass storage device 1428, the volatile memory 1414, the non-volatile memory 1416, and / or a removable, non-transitory computer-readable storage medium such as a CD or DVD.

[0183] A block diagram illustrating an example software distribution platform 1505 for distributing software, such as the example computer-readable instructions 1432 of FIG. 14, to third parties is shown in FIG. 15. The example software distribution platform 1505 may be implemented by any computer server, data facility, cloud service, etc., capable of storing and transmitting software to other computing devices. The third parties may be customers of the entity that owns and / or operates the software distribution platform. For example, the entity that owns and / or operates the software distribution platform may be a developer, seller, and / or licensor of software, such as the example computer-readable instructions 1432 of FIG. 14. The third parties may be consumers, users, retailers, OEMs, etc., that purchase and / or license software for use and / or resale and / or sublicense. In the illustrated example, the software distribution platform 1505 includes one or more servers and one or more storage devices. The storage devices store computer-readable instructions 1432, which may correspond to the example computer-readable instructions 1100 of FIGS. 11A and / or 11B, as described above. One or more servers of the exemplary software distribution platform 1505 are in communication with a network 1510, which may correspond to any one or more of the Internet and / or any of the exemplary networks described above. In some examples, the one or more servers are responsive to requests sent to parties requesting software as part of a commercial transaction. Payment for delivery, sales, and / or licenses of the software may be handled by one or more servers of the software distribution platform and / or through a third-party payment entity. The servers enable purchasers and / or licensors to download computer-readable instructions 1432 from the software distribution platform 1505.For example, software that may correspond to the example computer-readable instructions 1100 of Figures 11A and / or 11B can be downloaded to the example processor platform 1400, which executes the computer-readable instructions 1432 that implement the machine-readable LFA reader application 117 of Figures 1 and / or 6. In some examples, one or more servers of the software distribution platform 1505 periodically offer, transmit, and / or force updates to the software (e.g., the example computer-readable instructions 1432 of Figure 14) to ensure that improvements, patches, updates, etc. are distributed and applied to the software at end-user devices.

[0184]

[0010] Exemplary methods, apparatus, systems, and articles of manufacture for making and / or processing diagnostic test devices are disclosed herein. Further examples and combinations thereof include the following: Example 1 includes an apparatus for use with a fluid sample, the apparatus including a sensor that measures a current between a first electrode coupled to a first zone corresponding to a target analyte on a porous medium of the device and a second electrode coupled to a second zone of the porous medium of the device, a processor that compares the current to a threshold and identifies the target analyte as being present in the sample if the current exceeds the threshold, and an antenna that wirelessly transmits the result.

[0185] Example 2 includes the device of example 1, wherein the processor is to identify that the target analyte is not present in the sample if the current is below the threshold.

[0186] Example 3 includes the device of Example 1, wherein the porous membrane is for generating the current when the target analyte is present in the sample.

[0187] Example 4 includes the device of Example 1, wherein the sensor is for measuring a second current between a third electrode and a fourth electrode coupled to a control zone; the processor is for comparing the second current to the threshold and identifying the test as ready to be read if the second current is above the threshold; and the result includes an indication of whether the test is ready to be read.

[0188] Example 5 includes the apparatus of Example 4, wherein the control zone corresponds to at least one of an antibody, an analyte, or an antigen on the porous medium of the device.

[0189] Example 6 includes the device of example 1, wherein the antenna is for wirelessly transmitting the result to a reader.

[0190] Example 7 includes a method for use with a fluid sample, the method including measuring a current between a first electrode coupled to a first zone corresponding to a target analyte on a porous medium of a test strip and a second electrode coupled to a second zone of the porous medium of the test strip, comparing the current to a threshold value by executing instructions on a processor, identifying that the target analyte is present in the sample if the current exceeds the threshold value, and wirelessly transmitting a result.

[0191] Example 8 includes the method of example 7, further including identifying the target analyte as absent from the sample if the current is below the threshold.

[0192] Example 9 includes the method of example 7, wherein the current is generated when the target analyte is present in the sample.

[0193] Example 10 includes the method of Example 7, further including measuring a second current between a third electrode and a fourth electrode coupled to the test zone corresponding to a control zone; comparing the second current to the threshold; and identifying the test as ready to be read if the second current is above the threshold, wherein the result includes an indication of whether the test is ready to be read.

[0194] Example 11 includes the method of example 10, wherein the control zone corresponds to at least one of an analyte, an analyte, or an antibody on the porous medium of the test strip.

[0195] Example 12 includes the method of example 7, further including wirelessly transmitting the result to a reader.

[0196] Example 13 includes a device for use with a fluid sample, the device including: a conjugate pad including a conjugate corresponding to a target analyte, the conjugate labeled with at least one of gold nanoparticles or glucose oxidase; a test zone including at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte; and a bioelectrochemical cell that generates a current when the target analyte is present in the sample.

[0197] Example 14 includes the device of Example 13, wherein the bioelectrochemical cell is impregnated with at least one of an enzyme substrate, a reducing agent, an electron mediator, or a redox species.

[0198] Example 15 includes the device of Example 14, wherein the conjugate is capable of mixing with the at least one of the enzyme substrate, the reducing agent, the electron mediator, or the redox species to generate the current.

[0199] Example 16 includes the device of Example 13, wherein the bioelectrochemical cell is fluidly coupled to the test zone.

[0200] Example 17 includes the device of Example 13, wherein the bioelectrochemical cell is structured to be fluidly coupled to the test zone after user intervention.

[0201] Example 18 includes the device of Example 13, further including an inlet for separating the bioelectrochemical cell into a first portion and a second portion, the inlet allowing a buffer to enter the inlet and resuspend dried reagents in the bioelectrochemical cell, the resuspension generating the current in the bioelectrochemical cell.

[0202] Example 19 includes the device of Example 13, wherein the bioelectrochemical cell is a concentration cell.

[0203] Example 20 includes the device of example 13, further including a wireless chip coupled to a first end of the bioelectrochemical cell and a second end of the bioelectrochemical cell.

[0204] Example 21 includes the device of Example 20, wherein the wireless chip is for sensing the current between the first end and the second end to identify whether the target analyte is present in the sample.

[0205] Example 22 includes the device of Example 21, further including a sensor for determining a result based on the current drop across the bioelectrochemical cell, the result indicating the target analyte is present in the sample, and the wireless chip wirelessly transmits the result to a reader.

[0206] Example 23 includes the device of Example 22, wherein the reader is a smartphone application.

[0207] Example 24 includes the device of Example 13, wherein the bioelectrochemical cell is for generating a reaction that results in the production of hydrogen peroxide, and the device further includes an electrode coupled to the bioelectrochemical cell, the electrode being made from at least one of ferrocyanide-doped copper or screen-printed carbon, wherein oxidation of the at least one of the ferrocyanide-doped copper or screen-printed carbon and reduction of the hydrogen peroxide releases electrons corresponding to the current.

[0208] Example 25 includes a device for use with a fluid sample, the device including a sensor for measuring resistance between a first electrode coupled to a first end of a test line corresponding to a target analyte and a second electrode coupled to a second end of the test line, the test line being on a porous medium; a processor for comparing the resistance to a threshold and identifying the target analyte as being present in the sample if the resistance exceeds the threshold; and an antenna for wirelessly transmitting a result corresponding to the identification.

[0209] Example 26 includes the device of Example 25, wherein the processor is to identify that the target analyte is not present in the sample if the resistance is below the threshold.

[0210] Example 27 includes the device of Example 25, wherein the test line is connected when the target analyte is present in the sample and is an open circuit when the target analyte is not present in the sample.

[0211] Example 28 includes the device of Example 25, wherein when the target analyte is present in the sample and silver is applied to the test line, the silver amplifies at the test line until the silver creates a connection between the first electrode and the second electrode.

[0212] Example 29 includes the device of Example 25, further including a driver that outputs a voltage to at least one of the first electrode or the second electrode, the voltage driving a current between the first electrode and the second electrode, the current corresponding to the resistance.

[0213] Example 30 includes the device of Example 25, wherein the resistance is a first resistance; the sensor is for measuring a second resistance between the first end and the second end of the control line; the processor is for comparing the second resistance to the threshold and identifying the test as ready to be read if the second resistance exceeds the threshold; and the result includes an indication of whether the test is ready to be read.

[0214] Example 31 includes the device of Example 30, wherein the control line corresponds to an excess of analyte on the porous medium.

[0215] Example 32 includes a method for use with a fluid sample, the method including measuring a resistance between a first electrode coupled to a first end of a test line corresponding to a target analyte and a second electrode coupled to a second end of the test line, the test line being on a porous medium; comparing the resistance to a threshold by executing instructions on a processor; identifying the target analyte as present in the sample if the resistance exceeds the threshold; and wirelessly transmitting a result corresponding to the identification.

[0216] Example 33 includes the method of Example 32, further including identifying the target analyte as absent from the sample if the resistance is below the threshold.

[0217] Example 34 includes the method of example 32, wherein the test line is connected when the target analyte is present in the sample and is an open circuit when the target analyte is not present in the sample.

[0218] Example 35 includes the method of Example 32, wherein when the target analyte is present in the sample and silver is applied to the test line, the silver amplifies at the test line until the silver creates a connection between the first electrode and the second electrode.

[0219] Example 36 includes the method of Example 32, further including outputting a voltage to at least one of the first electrode or the second electrode, the voltage causing a current corresponding to the resistance to flow between the first electrode and the second electrode.

[0220] Example 37 includes the method of Example 32, wherein the resistance is a first resistance, the method further including measuring a second resistance between the first end and the second end of the control line, comparing the second resistance to the threshold, and identifying the test as ready to be read if the second resistance is above the threshold, wherein the identifying includes an indication of whether the test is ready to be read.

[0221] Example 38 includes the method of Example 37, wherein the control line corresponds to an excess of analyte on the porous medium.

[0222] Example 39 includes a device for use with a fluid sample, the device including: a conjugate pad including a conjugate corresponding to a target analyte, the conjugate labeled with gold; and a test zone including at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte, the test zone immobilizing the gold in the test zone and amplifying silver onto the gold when a solution is applied to the test zone.

[0223] Example 40 includes the device of Example 39, further including a first electrode coupled to a first section of the test zone and a second electrode coupled to a second section of the test zone, wherein when the silver amplifies to above a threshold size, a connection is formed between the first electrode and the second electrode.

[0224] Example 41 includes the device of Example 39, further including a wireless chip coupled to a first end of the test zone and a second end of the test zone, the wireless chip including a driver for applying a voltage to the first end of the test zone.

[0225] Example 42 includes the device of Example 41, wherein the wireless chip includes a sensor for sensing a voltage drop across the first end and the second end, and a processor for identifying whether the target analyte is present in the sample based on the voltage drop.

[0226] Example 43 includes the device of Example 42, further including an antenna coupled to the wireless chip, the antenna wirelessly transmitting a result to a reader, the result corresponding to whether the target analyte is present in the sample.

[0227] Example 44 includes the device of example 43, wherein the reader is a smartphone application.

[0228] Example 45 includes the device of Example 43, wherein the antenna is wrapped around the wireless chip, the conjugate pad, and the test zone.

[0229] Example 46 includes a method, the method including obtaining results for a fluid sample-based test from a wireless chip on a device, displaying the results on a user interface, and transmitting the results and corresponding information to at least one of an external database or an external server.

[0230] Example 47 includes the method of example 46, wherein the results are not displayed or indicated on the device, and wherein obtaining the results includes obtaining the results in a machine-readable format from the device.

[0231] Example 48 includes the method of Example 46, wherein the corresponding information includes at least one of a patient identifier, a device identifier, a timestamp, a number of test readings, location information, or demographic information.

[0232] Example 49 includes the method of example 46, further including displaying a reading instruction on the user interface.

[0233] Example 50 includes the method of Example 46, further including, in response to receiving timing information from the wireless chip, displaying via the user interface a time until the device is ready to read.

[0234] Example 51 includes the method of example 46, wherein the result identifies whether a sample provided to the device tested positive or negative for a disease or condition.

[0235] Example 52 includes a non-transitory computer-readable storage medium having instructions that, when executed, cause a machine to at least obtain results of a fluid sample-based test from a wireless chip on the device, display the results on a user interface, and transmit the results and corresponding information to at least one of an external database or an external server.

[0236] Example 53 includes the computer-readable storage medium of Example 52, wherein the results are not displayed or shown on the device, and the instructions, when executed, cause the machine to obtain the results in machine-readable format from the device.

[0237] Example 54 includes the computer-readable storage medium of Example 52, wherein the corresponding information includes at least one of a patient identifier, a device identifier, a timestamp, a number of test readings, location information, or demographic information.

[0238] Example 55 includes the computer-readable storage medium of Example 52, wherein the instructions cause the machine to display reading instructions on the user interface.

[0239] Example 56 includes the computer-readable storage medium of Example 52, wherein the instructions cause the machine to display, via the user interface, a time until the device is ready to be read, in response to receiving timing information from the wireless chip.

[0240] Example 57 includes the computer-readable storage medium of Example 52, wherein the result indicates whether a sample provided to the device tested positive or negative for a disease or condition.

[0241] Example 58 includes an apparatus, the apparatus including an antenna for obtaining results for a fluid sample-based test from a wireless chip on a device, and a user interface for displaying the results, the antenna transmitting the results and corresponding information to at least one of an external database or an external server.

[0242] Example 59 includes the apparatus of example 58, wherein the results are not displayed or shown on the device, and the antenna is for obtaining the results in a machine-readable format from the device.

[0243] Example 60 includes the apparatus of example 58, wherein the corresponding information includes at least one of a patient identifier, a device identifier, a timestamp, a number of test readings, location information, or demographic information.

[0244] Example 61 includes the device of example 58, wherein the user interface is for displaying a reading instruction.

[0245] Example 62 includes the apparatus of example 58, wherein the user interface is for displaying a time until the device is ready to be read in response to receiving timing information from the wireless chip.

[0246] Example 63 includes the apparatus of Example 58, wherein the result indicates whether a sample provided to the device tests positive or negative for a disease or condition.

[0247] Example 64 includes a non-visual indicating device for use with a fluid sample, the non-visual indicating device including a timer for initiating in response to power received from a bioelectrochemical cell, and an interface for transmitting at least one of (A) a time indicated by the timer, or (B) a threshold duration when the time indicated by the timer falls below a threshold duration in response to sensing an electromagnetic field from an external device.

[0248] Example 65 includes the non-visual indicating device of Example 64, wherein the interface is for transmitting the at least one of the time indicated by the timer or the threshold duration to the device that generated the electromagnetic field.

[0249] Example 66 includes the non-visual indicating device of Example 64, wherein the threshold duration corresponds to an assay time.

[0250] Example 67 includes the non-visual indicating device of Example 64, wherein the time below the threshold duration corresponds to an incomplete assay.

[0251] Example 68 includes the non-visual indicating device of Example 64, wherein the bioelectrochemical cell is a first biofuel cell, and the non-visual indicating device further includes a comparator for determining whether a voltage drop across a second biofuel cell exceeds a threshold voltage when the time indicated by the timer exceeds the threshold duration.

[0252] Example 69 includes the non-visual indicating device of Example 68, wherein the interface is for transmitting a result to the device that generated the electromagnetic field based on the determination of whether the voltage drop exceeds the threshold voltage.

[0253] Example 70 includes a system, the system including a non-visible indicating device for transmitting a test result when an electromagnetic field is sensed, and a reader for generating the electromagnetic field, obtaining the test result, and transmitting the test result to at least one of an external database or an external server.

[0254] Example 71 includes the system of example 70, wherein the non-visual indicating device is for determining the test result based on at least one of a current or a voltage.

[0255] Example 72 includes the system of Example 71, wherein the non-visual indicating device includes a bioelectrochemical cell for generating the at least one of the current or the voltage.

[0256] Example 73 includes the system of example 70, wherein the non-visual indicating device includes a wireless chip for transmitting the test results.

[0257] Example 74 includes the system of example 70, wherein the electromagnetic field powers a wireless chip in the non-visual indicating device via an antenna of the non-visual indicating device.

[0258] Example 75 includes the system of example 74, wherein the antenna transmits the test results to the reader.

[0259] Example 76 includes the system of example 70, wherein the reader is implemented within a portable computing device.

[0260] Example 77 includes the system of example 70, wherein the reader displays the test results on a user interface.

[0261] Example 78 includes a device for use with a fluid sample, the device including: a conjugate pad containing a conjugate corresponding to a target analyte, the conjugate labeled with at least one of gold nanoparticles or glucose oxidase; a porous medium including a first zone and a second zone, the first zone containing at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte, generating a current from the first zone to the second zone when the target analyte is present in the sample; a first electrode in contact with the first zone; and a second electrode in contact with the second zone.

[0262] Example 79 includes the device of Example 78, wherein the porous medium is saturated with at least one of an enzyme substrate, a reducing agent, an electron mediator, or a redox species.

[0263] Example 80 includes the device of Example 79, wherein the conjugate is capable of mixing with the at least one of the enzyme substrate, the reducing agent, the electron mediator, or the redox species to generate the current.

[0264] Example 81 includes the device of Example 78, wherein the porous medium forms a bioelectrochemical cell.

[0265] Example 82 includes the device of example 78, further including a wireless chip coupled to the first electrode and the second electrode.

[0266] Example 83 includes the device of Example 82, wherein the wireless chip is for sensing the current between the first electrode and the second electrode to identify whether the target analyte is present in the sample.

[0267] Example 84 includes the device of Example 81, further including a sensor for determining a result based on the current from the first electrode and the second electrode, the result indicating the target analyte is present in the sample, and the wireless chip wirelessly transmits the result to a reader.

[0268] Example 85 includes the device of example 84, wherein the reader is a smartphone application.

[0269] Example 86 includes the device of Example 78, wherein the porous medium is non-compartmental.

[0270] Example 87 includes the device of Example 78, wherein a reaction occurs on the porous medium to produce hydrogen peroxide, at least one of the first electrode or the second electrode is made from at least one of ferrocyanide-doped copper or screen-printed carbon, and the at least one of the ferrocyanide-doped copper or screen-printed carbon is oxidized and the hydrogen peroxide is reduced, releasing electrons corresponding to the current.

[0271] Example 88 includes a system comprising a non-visible indicating biosensor device for transmitting a test result when an electromagnetic field is sensed, and a reader for generating said electromagnetic field and obtaining said test result.

[0272] Example 89 includes the system of Example 88, wherein the non-visual indicator biosensor device includes a bioelectrochemical cell for generating a current when a target analyte is present in a sample.

[0273] Example 90 includes the system of Example 88, wherein the non-visual indicator biosensor device generates the test result based on a current between a first portion of a bioelectrochemical cell and a second portion of the bioelectrochemical cell, the bioelectrochemical cell being contained within the non-visual indicator biosensor device.

[0274] Example 91 includes the system of Example 88, wherein the non-visual indicator biosensor device includes a porous medium having a first zone and a second zone, and the test result is based on a current between the first zone and the second zone.

[0275] Example 92 includes the system of Example 88, wherein the non-visual indicator biosensor device includes a porous medium having a test zone, and the non-visual indicator biosensor device determines the test result based on a current passing through the test zone.

[0276] Example 93 includes the system of example 88, wherein the reader is a smartphone.

[0277] Example 94 includes the system of example 88, wherein the reader is for transmitting the test results to an external database.

[0278] Example 95 includes a non-visual indicator biosensor device for use with a fluid sample, the non-visual indicator biosensor device including a lateral flow test strip for testing a target analyte in the sample and an antenna for sensing an electromagnetic field from an external device, the electromagnetic field inducing a current in the biosensor device to operate the test and transmitting the test results to the external device.

[0279] Example 96 includes the device of Example 95, wherein the lateral flow test strip includes a bioelectrochemical cell for generating an electric current when the target analyte is present in the sample.

[0280] Example 97 includes the device of Example 96, wherein the current is between the first portion of the bioelectrochemical cell and the second portion of the bioelectrochemical cell.

[0281] Example 98 includes the device of Example 95, wherein the lateral flow test strip includes a porous medium having a first zone and a second zone, and the test result is based on a current between the first zone and the second zone.

[0282] Example 99 includes the device of Example 95, wherein the lateral flow test strip includes a porous medium having a test zone, and the test result is based on a current passing through the test zone.

[0283] Example 100 includes a system comprising a non-visible indicating biosensor device for transmitting the result of a test and a reader for timing the test and obtaining the result of the test after a certain time has elapsed since the start of the test.

[0284] Example 101 includes the system of Example 100, wherein the non-visual indicator biosensor device includes a timer that starts when the test is initiated.

[0285] Example 102 includes the system of Example 100, wherein the non-visible indicator biosensor device is for transmitting to the reader at least one of (a) a start time corresponding to the start of the test, or (b) a time indicated by the timer.

[0286] Example 103 includes the system of Example 102, wherein the reader is to display at least one of the start time, the time indicated by the timer, or the time until the test is completed.

[0287] Example 104 includes the system of Example 101, wherein the test is initiated when a wireless chip of the non-visual indicator biosensor device receives power.

[0288] Example 105 includes a biosensor for providing a diagnostic result, the biosensor including an area for receiving a biological sample to be tested, a test area that generates a current in a circuit if a target analyte is present in the biological sample, and an antenna for wirelessly transmitting information associated with the target analyte when presented to a reader, the biosensor being powered by a bioelectrochemical cell in contact with the test area.

[0289] Example 106 includes the biosensor of Example 105, wherein molecules in the test region are for reacting with molecules in the bioelectrochemical cell to generate the current.

[0290] Example 107 includes the biosensor of Example 105, further including a chip for measuring an electromotive force corresponding to the current and generating the information related to the target analyte based on the current.

[0291] Example 108 includes the biosensor of Example 107, wherein the electromotive force is for powering the biosensor.

[0292] Example 109 includes the biosensor of Example 105, wherein the antenna is for sensing a magnetic field of the reader.

[0293] Example 110 includes a biosensor for providing a diagnostic result, the biosensor including an area for receiving a biological sample to be tested, a test area for generating a current in a circuit if a target analyte is present in the biological sample, and an antenna for wirelessly transmitting information related to the target analyte when presented to a reader, the antenna being powered by a magnetic field generated by the reader.

[0294] Example 111 includes the biosensor of Example 110, wherein the molecules on the test area are for reacting with molecules in a bioelectrochemical cell to generate the current.

[0295] Example 112 includes the biosensor of Example 108, further including a chip for measuring an electromotive force corresponding to the current and generating the information related to the target analyte based on the current.

[0296] Example 113 includes the biosensor of Example 112, wherein the electromotive force is for powering the biosensor.

[0297] Example 114 includes the biosensor of Example 110, wherein the antenna is for sensing the magnetic field of the reader.

[0298] Example 115 includes an apparatus, the apparatus including: a front end for connecting to one or more electrodes of a biosensor on a lateral flow immunoassay device and acquiring one or more signals from the one or more electrodes; and a wireless chip for acquiring the one or more signals from the front end, determining a result of a test based on the presence or absence of one or more target analytes in a sample based on the acquired one or more signals, and wirelessly transmitting the result to a computing device.

[0299] Example 116 includes the device of Example 115, wherein the front end includes a first front end input for obtaining a first signal of the one or more signals from a first electrode of the one or more electrodes, a second front end input for obtaining a second signal of the one or more signals from a second electrode of the one or more electrodes, and an output for outputting at least one of the first signal or the second signal based on instructions from the wireless chip.

[0300] Example 117 includes the apparatus of Example 116, wherein the wireless chip includes a first chip input for obtaining the output of the front end, where the wireless chip compares the output of the front end to a first signal strength threshold, and a second chip input for obtaining the output of the front end, where the wireless chip compares the output of the front end to a second signal strength threshold.

[0301] Example 118 includes the apparatus of Example 115, wherein the wireless chip includes a first chip input and a second chip input, and the front end includes a front end input for connecting to one of the one or more electrodes to acquire one of the one or more signals based on instructions from the wireless chip, and a front end output for transmitting the acquired signal of the one or more signals to one of the first input or the second input of the wireless chip based on the instructions from the wireless chip.

[0302] Example 119 includes the device of Example 115, wherein the wireless chip includes a first chip input and a second chip input, and the front end includes a first channel for connecting a first electrode of the one or more electrodes to the first input of the wireless chip, and a second channel for connecting a second electrode of the one or more electrodes to the second input of the wireless chip.

[0303] Example 120 includes an apparatus for use with a fluid sample, the apparatus including a porous medium, an absorbent pad in contact with the porous medium, and a switch having a flow arrester for at least one of compressing or shearing the porous medium and at least one of reducing or stopping the flow of liquid toward the absorbent pad.

[0304] Example 121 includes the apparatus of Example 120, wherein the switch moves from a first position to a second position to at least one of compress or shear the porous medium.

[0305] Example 122 includes the device of Example 121, further including an electrode, wherein the switch causes the electrode to contact the porous medium while the switch is in the second position.

[0306] Example 123 includes the device of Example 121, wherein the switch is a first distance from the porous medium in the first position and a second distance from the porous medium in the second position, the second distance being less than the first distance.

[0307] Example 124 includes the device of Example 120, further comprising a holding component comprising a buffer.

[0308] Example 125 includes the device of Example 124, wherein the switch causes the holding component to release the buffer onto the porous medium.

[0309] Example 126 includes a lateral flow assay device, the lateral flow assay device including: a conjugate pad including a conjugate corresponding to a target analyte in a biological sample, the conjugate being labeled with an enzyme; a porous medium including a first zone and a second zone, the first zone including at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte, the second zone being displaced outward from the first zone along a longitudinal axis of the lateral flow assay device, the porous medium propagating a flow rate of the biological sample, the conjugate including the enzyme, and a buffer solution along the porous medium; a first electrode contacting the porous medium in the first zone; and a second electrode contacting the porous medium in the second zone, the first electrode and the second electrode detecting an electrical signal when the target analyte is present in the biological sample and the enzyme reacts with the buffer solution; and a positionable flow arrester that obstructs the flow rate in the second zone.

[0310] Example 127 includes the lateral flow assay device of Example 126, further including an absorbent pad coupled to the porous medium, wherein the flow arrester is for at least one of compressing or shearing the porous medium to at least one of reducing or stopping the flow rate toward the absorbent pad.

[0311] Example 128 includes the lateral flow assay device of Example 127, wherein the flow arrester includes a switch movable from a first position to a second position to perform at least one of compression or shear on the porous medium.

[0312] Example 129 includes the lateral flow assay device of Example 128, wherein moving the switch to the second position causes the first electrode and the second electrode to contact the porous medium.

[0313] Example 130 includes the lateral flow assay device of Example 128, wherein the switch is a first distance from the porous medium in the first position and a second distance from the porous medium in the second position, the second distance being shorter than the first distance.

[0314] Example 131 includes the lateral flow assay device of Example 128, further comprising a circuit board, wherein the first electrode and the second electrode are coupled to the circuit board, and the switch moves at least a portion of the circuit board into proximity with the porous medium.

[0315] Example 132 includes the lateral flow assay device of Example 131, wherein the circuit board is pivotable, and when the switch is moved, the switch pivots the circuit board.

[0316] Example 133 includes the lateral flow assay device of any of Examples 127 to 132, wherein the flow arrester includes a first flow arrester and a second flow arrester.

[0317] Example 134 includes the lateral flow assay device of Example 133, wherein the first flow arrestor is for at least one of compressing or shearing the porous medium in the first zone, and the second flow arrestor is for at least one of compressing or shearing the porous medium in the second zone.

[0318] Example 135 includes the lateral flow assay device of Example 134, wherein the first electrode and the second electrode are positioned between the first flow arrestor and the second flow arrestor.

[0319] Example 136 includes the lateral flow assay device of any of Examples 126-135, wherein the flow arrester includes a chemical that forms a barrier when wetted.

[0320] Example 137 includes the lateral flow assay device of any of Examples 126 to 136, further comprising an antenna in a circuit including the first electrode and the second electrode, the antenna transmitting a radio signal representing the electrical signal to an external device.

[0321] Example 138 includes the lateral assay device of any of Examples 126-137, further including: an antenna in a circuit including the first electrode and the second electrode, the antenna receiving a power signal from the external device; a sensor for measuring at least one of a voltage or a current between the first electrode and the second electrode, the sensor operable based on the power signal, the at least one of the voltage or the current being the electrical signal; and a processor operable based on the power signal, the processor comparing the at least one of the voltage or the current to a threshold value, and identifying that the target analyte is present in the biological sample if the at least one of the voltage or the current exceeds the threshold value, and the antenna wirelessly transmitting the result to the external device.

[0322] Example 139 includes the lateral assay device of any of Examples 126-138, wherein the electrical signal is generated by an enzymatic reaction.

[0323] Example 140 includes the lateral assay device of any of Examples 126-139, wherein the lateral assay device is battery-less.

[0324] Example 141 includes an apparatus for use with a fluid sample, the apparatus including a porous medium, an absorbent pad in contact with the porous medium, and a switch having a flow arrester for at least one of compressing or shearing the porous medium and at least one of reducing or stopping the flow of liquid toward the absorbent pad.

[0325] Example 142 includes the apparatus of Example 141, wherein the switch is movable between a first position and a second position to at least one of compress or shear the porous medium.

[0326] Example 143 includes the device of Example 142, further including an electrode, wherein the switch contacts the electrode with the porous medium while the switch is in the second position.

[0327] Example 144 includes the device of Examples 142 or 143, wherein the switch is a first distance from the porous medium in the first position and a second distance from the porous medium in the second position, the second distance being less than the first distance.

[0328] Example 145 includes the device of any of Examples 141-144, further comprising a reservoir containing a buffer solution, wherein the switch causes the reservoir to release the buffer solution onto the porous medium.

[0329] Example 146 includes the apparatus of any of Examples 141-145, wherein the flow arrestor is for shearing the porous medium by cutting a portion of the depth of the porous medium.

[0330] Example 147 includes a non-visual indicator biosensor, the non-visual indicator biosensor including: a conjugate pad including a conjugate that attaches to a target analyte in a biological sample, the conjugate being labeled with an enzyme; a porous medium having a first end and a second end, the conjugate pad being coupled to the first end of the porous medium; at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte being coupled to the porous medium between the first end and the second end, the porous medium implementing a bioelectrochemical cell between the first end and the second end downstream from the at least one of the immobilized antigen or the immobilized antibody, the bioelectrochemical cell generating an electrical signal based on a reaction between a buffer solution and the enzyme when the target analyte is present in the biological sample; an absorbent pad for drawing fluid along the porous medium; and an antenna for generating a wireless signal to communicate the presence of the electrical signal.

[0331] Example 148 includes the non-visual indicator biosensor of Example 147, further comprising a circuit board selectively engageable with the porous medium, the circuit board including a first electrode and a second electrode downstream from the first electrode, and the electrical signal is generated based on at least one of a voltage difference between the first electrode and the second electrode or a current between the first electrode and the second electrode.

[0332] Example 149 includes the non-visual indicator biosensor of Example 148, further including a processor, wherein the processor compares the magnitude of the voltage difference or the current to a threshold and identifies the target analyte as being present in the biological sample if the magnitude meets the threshold.

[0333] Example 150 includes the non-visual indicator biosensor of Example 149, wherein the antenna is for receiving a power signal to operate the antenna and the processor.

[0334] Example 151 includes the non-visual indicator biosensor of any of Examples 147-150, further including a switch movable between a first position and a second position, wherein movement of the switch from the first position to the second position changes the non-visual indicator biosensor from a first operating mode to a second operating mode.

[0335] Example 152 includes the non-visual indicating biosensor of Example 151, wherein the switch includes a flow arrestor that at least one of cuts or compresses the porous medium when the switch is in the second position, and liquid is allowed to flow to the absorbent pad during the first mode of operation and liquid flow is stopped during the second mode of operation.

[0336] Example 153 includes the non-visual indicator biosensor of Examples 151 or 152, wherein when the switch moves from the first position to the second position, an electrode moves from disengaged from the porous medium to engaged with the porous medium.

[0337] Example 154 includes the non-visible indicator biosensor of any of Examples 147-153, wherein the antenna is for sensing a first electromagnetic field from an external device at a first time and providing identification data of the non-visible indicator biosensor to the external device in response to sensing the first electromagnetic field, and for sensing a second electromagnetic field from the external device at a second time and providing the wireless signal in response to sensing the second electromagnetic field to communicate the presence of the electrical signal to the external device.

[0338] Example 155 includes the non-visible indicator biosensor of Example 154, wherein the antenna is for sensing a third electromagnetic field from the external device at a third time, the third time being between the first time and the second time, and for providing the identification data to the external device in response to sensing the third electromagnetic field.

[0339] Example 156 includes the non-visual indicator biosensor of Examples 147 or 151-155, wherein the antenna is for providing a signal corresponding to at least one of a voltage or a current generated in the porous medium, the at least one of the voltage or the current being generated by an enzymatic reaction between the enzyme and the buffer solution.

[0340] Example 157 includes at least one non-transitory computer-readable medium containing instructions that, when executed, cause one or more processors to at least: access identification information received from a lateral flow assay device at a first time; implement a counter for monitoring a first time period and a second time period, the first time period and the second time period being based on the identification information; command a change from a first operational mode of the lateral flow assay device to a second operational mode of the lateral flow assay device after the first time period and during the second time period; access at least one of a voltage value or a current value received from the lateral flow assay device via near field communication (NFC) at a second time, the second time being after the second time period; compare the voltage value or the current value to a threshold value, the threshold value being based on the identification information; and identify a diagnostic test result based on the comparison.

[0341] Example 158 includes the at least one non-transitory computer-readable medium of Example 157, wherein the instructions cause the one or more processors to determine a geographic location of the lateral flow assay device and tag the diagnostic test results with the geographic location of the lateral flow assay device.

[0342] Example 159 includes the at least one non-transitory computer-readable medium of Example 157, wherein the lateral flow assay device is a first lateral flow assay device, the identification information is a first identification information, the voltage value is a first voltage value, the current value is a first current value, the comparison is a first comparison, the threshold is a first threshold, and the diagnostic test result is a first diagnostic test result; and the instructions cause the one or more processors to access second identification information received from a second lateral flow assay device via the NFC at a third time; and monitor, using the counter, a third time period and a fourth time period, wherein the third time period and the fourth time period are based on the second identification information. and performing a second comparison of the second voltage value or the second current value with a second threshold value, the second threshold value being based on the second identification information.

[0343] Example 160 includes the at least one non-transitory computer-readable medium of Example 159, wherein one or more of: (1) the third time period at least partially overlaps with one or more of the first time period or the second time period; or (2) the fourth time period at least partially overlaps with one or more of the first time period or the second time period.

[0344] Example 161 includes the at least one non-transitory computer-readable medium of Example 157, wherein the identification information is first identification information, the lateral flow assay device is a first lateral flow assay device, and the instructions cause the one or more processors to access second identification information received from a second lateral flow assay device via near field communication (NFC) prior to the instruction to change from the first operating mode to the second operating mode, after the first time, and at a first third time before the second time.

[0345] Example 162 includes the at least one non-transitory computer-readable medium of Example 161, wherein the instructions cause the one or more processors to command the change from the first operating mode to the second operating mode if the first identification information matches the second identification information, and the first lateral flow device is the second lateral flow device.

[0346] Example 163 includes the at least one non-transitory computer-readable medium of Example 161, wherein if the first identification information does not match the second identification information, the instructions cause the one or more processors to display an indication that the second lateral flow device is not the first lateral flow device and prompt a user to scan the first lateral flow device via the NFC.

[0347] Example 164 includes the at least one non-transitory computer-readable medium of Example 157, wherein the identification information is a first identification information, and the instructions cause the one or more processors to tag the diagnostic test result as void if a second identification information matching the first identification information is not obtained from the lateral flow assay device within the first period of time.

[0348] Example 165 includes the at least one non-transitory computer-readable medium of Example 157, wherein the instructions cause the one or more processors to tag the diagnostic test result as void if confirmation of the change from the first operating mode to the second operating mode is not obtained within the second time period.

[0349] Example 166 includes the at least one non-transitory computer-readable medium of any of Examples 157-165, wherein the at least one of the voltage or the current is detected wirelessly by the NFC.

[0350] Example 167 includes the at least one non-transitory computer-readable medium of Example 157, wherein the instructions cause the one or more processors to wirelessly transmit the diagnostic test results and corresponding patient data to at least one of a remote database or a remote server.

[0351] Example 168 includes at least one non-transitory computer-readable medium containing instructions that, when executed, cause one or more processors to at least: access first identification information received from a lateral flow assay device via a near field communication (NFC) scan at a first time; implement a counter to monitor a first period of time, the first period of time being based on the identification information; access second identification information via a second NFC scan at a second time after the first time before an end of the first period of time; compare the first identification information to the second identification information; and if the first identification information matches the second identification information, access at least one of a voltage value or a current value received from the lateral flow assay device via a third NFC scan at a third time, the third time being the second time; and identify a diagnostic test result based on the at least one of the voltage value or the current value.

[0352] Example 169 includes at least one non-transitory computer-readable medium containing instructions that, when executed, cause one or more processors to at least access identification information corresponding to a lateral flow assay device; implement a counter to monitor a period of time; instruct a user to scan the lateral flow assay device using near field communication (NFC) after the period of time; access at least one of a voltage value or a current value received from the lateral flow assay device via the scan; compare the voltage value or the current value to a threshold value, where the threshold value is based on the identification information; and determine a diagnostic test result based on the comparison.

[0353] Example 170 includes the at least one non-transitory computer-readable medium of Example 169, wherein the instructions cause the one or more processors to guide the user to apply at least one of a sample or a buffer to the lateral flow assay device and perform the counter after the user confirms that the at least one of the sample or the buffer has been applied.

[0354] Example 171 includes the at least one non-transitory computer-readable medium of Example 169, wherein the instructions cause the one or more processors to instruct the user to scan the lateral flow assay using the NFC to obtain the identification information.

[0355] Example 172 includes the at least one non-transitory computer-readable medium of Example 169, wherein the instructions cause the one or more processors to instruct a user to scan the lateral flow assay using the NFC at a time prior to the access of the at least one of the voltage value or the current value.

[0356] Example 173 includes the at least one non-transitory computer-readable medium of Example 172, wherein the identification information is a first identification information, and the instructions cause the one or more processors to access second identification information via the NFC in response to the scan at the second time, compare the second identification information to the first identification information, and alert a user of an error if the second identification information does not match the first identification information.

[0357] Example 174 includes a method for determining the presence or absence of a target analyte in a biological sample, the method including instructing a user via an interface of a user device to apply the biological sample to a lateral flow device; generating a test result by executing instructions on a processor of the user device to determine whether the target analyte is present in the biological sample based on electrical signals wirelessly received from the lateral flow device; and transmitting the test result from the user device to at least one of an external server or an external database.

[0358] Example 175 includes the method of Example 174, wherein the electrical signal corresponds to an enzymatic reaction on the lateral flow device.

[0359] Example 176 includes the method of Example 174, further including instructing the user via the interface to take action to stop flow on the lateral flow device.

[0360] Example 177 includes the method of example 176, wherein stopping the flow enhances the electrical signal.

[0361] Example 178 includes the method of Example 176, further including implementing a timer via the user device, wherein instructing the user to take the action to stop the flow rate is based on an output of the timer.

[0362] Example 179 includes the method of Example 174, wherein generating the test result includes comparing the electrical signal to a threshold value by executing instructions on the processor, and the electrical signal is at least one of a voltage or a current generated across a porous membrane of the lateral flow device.

[0363] Example 180 includes the method of Example 174, further including preventing display of the test results on the interface of the user device to protect patient privacy.

[0364] Example 181 includes the method of Example 174, further including: executing instructions on the processor to obtain a first identifier from the lateral flow device at a first time before instructing the user to apply the biological sample; and executing instructions on the processor to obtain a second identifier from the lateral flow device before obtaining the electrical signal.

[0365] Example 182 includes the method of Example 181, further including identifying an algorithm based on the first identifier by executing instructions on the processor, wherein determining whether the target analyte is present in the biological sample is based on the algorithm.

[0366] Example 183 includes the method of Example 181, further including validating that the electrical signal corresponds to the lateral flow device if the first identifier matches the second identifier by executing instructions on the processor.

[0367] Example 184 includes the method of example 174, wherein transmitting the test results includes transmitting the test results along with patient information and geographic location information.

[0368] The disclosed methods, devices, and articles of manufacture improve the efficiency of determining the results of machine-readable diagnostic tests. To mitigate and / or otherwise eliminate ambient light issues, examples disclosed herein provide machine-readable diagnostics that can be read with a smartphone rather than visually. Thus, the disclosed methods, devices, and articles of manufacture are directed to one or more improvement(s) in the functionality of diagnostic tests and diagnostic readers.

[0369] Furthermore, as mentioned above, visual interpretation of test results is prone to operator subjectivity and error. More accurate and objective results can be obtained using the electrical-based examples disclosed herein. Examples disclosed herein include LFA devices that generate electrical signals (e.g., current, voltage, etc.) corresponding to test results using various technologies (e.g., bioelectrochemical cell technology, circuit completion technology, etc.). The electrical signals can be measured without a battery device included in the LFA device and provided wirelessly to a reader. In some examples, the LFA device can determine a test result based on the electrical signal and transmit the result to the reader. The reader can obtain the test results and / or process the electrical signal to determine the test result and distribute the test results to an external server or database (e.g., via the reader) to provide near real-time data corresponding to disease and / or disease prevalence.

[0370] Additionally, examples disclosed herein provide mechanisms for stopping the flow and / or positioning electrodes on the LFA device to obtain a stronger electrical signal that can be measured for a longer duration than other diagnostic tests. Examples disclosed herein also enable multiplexing, which can use multiple lines to detect multiple marks (e.g., multiple types of antibodies / antigens) based on a single sample that would be difficult or impossible to interpret with the human eye. Multiplexing has applications, for example, in a single diagnostic test that can test for multiple types of sexually transmitted diseases.

[0371] The example controls disclosed herein also control the runtime of diagnostic tests to ensure that the operator does not attempt to obtain results too early (i.e., before the test is completed), obtain results too late, stop flow too early, stop flow too late, etc. This allows for further error prevention when obtaining accurate test results. Furthermore, the example controls facilitate multiple scans: (a) a scan to identify the LFA device, (b) a scan to verify that the test being read corresponds to the test that was supposed to be read (e.g., when running multiple tests in parallel on different LFAs using a single reader), and (c) a scan to obtain electrical signals corresponding to the test results. This allows for further error prevention when obtaining multiple tests with overlapping read windows, thereby ensuring that the wrong test is not read.

[0372] The examples disclosed herein also include additional information (such as lot number, use by date, expiration date, test information, signal quality information, chain of custody, etc.) along with the test results, all of which can be transferred together using NFC technology. Conventional methods use an additional reader, such as a barcode reader, to read information about the test in addition to the optical reader that determines / interprets the test result. Thus, the disclosed examples reduce the number of readers required to obtain more information.

[0373] Additionally, examples of rapid diagnostic tests using electronic-based approaches are more sensitive than traditional visually read tests. In the examples disclosed herein, lower detection thresholds are possible using electronic-based techniques than can be used when results are based on the visual interpretation of an operator.

[0374] Examples disclosed herein may include an NFC chip that can be encoded and encrypted. The associated test and manufacturing specific data can then be re-coded if adjustments are made to the product identification data, including, for example, extending the shelf life, and / or other retrofits are desired. In some examples, the encoding and / or encryption can be updated and / or remotely configured.

[0375] Descriptive terms such as "first," "second," and "third" are used herein to identify multiple elements or components that may be referenced separately. Unless otherwise specified or understood based on the context of usage, such descriptive terms are not intended to imply any sense of priority, physical order or placement within a list, or order in time, but are merely used as labels to refer to multiple elements or components separately to facilitate understanding of the examples of this disclosure. In some instances, the descriptive term "first" may be used to refer to an element in the Detailed Description, while the same element may be referred to in the claims using a different descriptive term such as "second" or "third." In such instances, it should be understood that such descriptive terms are used merely for ease of reference to multiple elements or components.

[0376] The terms "comprise" and "comprises" (and all their forms and tenses) are used herein as open-ended terms. Thus, whenever a claim uses any form of "include" or "comprise" (e.g., comprises, includes, comprising, including, having, etc.) as a preamble or within any type of claim description, it is to be understood that additional elements, terms, etc. may be present without departing from the scope of the corresponding claim or description. As used herein, for example, in the preamble of a claim, the term "at least" is open-ended in the same way that the terms "comprise" and "comprises" are open-ended when used as a transitional term. The term "and / or," when used in the form A, B, and / or C, for example, refers to any combination or subset of A, B, and C, such as (1) A alone, (2) B alone, (3) C alone, (4) A and B, (5) A and C, (6) B and C, and (7) A, B, and C. When used herein in the context of describing a structure, component, article, object, and / or thing, the phrase "at least one of A and B" is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. Similarly, when used herein in the context of describing a structure, component, article, object, and / or thing, the phrase "at least one of A or B" is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B. When used herein in the context of describing the performance or execution of a process, instruction, action, activity, and / or step, the phrase "at least one of A and B" is intended to refer to an implementation that includes either (1) at least one A, (2) at least one B, or (3) at least one A and at least one B.Similarly, when used herein in the context of describing the performance or execution of a process, instruction, action, activity, and / or step, the phrase "at least one of A or B" is intended to refer to implementations that include either (1) at least one A, (2) at least one B, and (3) at least one A and at least one B.

[0377] As used herein, singular references (e.g., "a," "an," "first," "second," etc.) do not exclude plural references. As used herein, the term "a" or "an" entity refers to one or more of that entity. The terms "a" (or "an"), "one or more," and "at least one" can be used interchangeably herein. Furthermore, although individually described, actions of a plurality of means, elements, or methods may be implemented by, for example, a single unit or processor. Furthermore, although individual features may be included in different examples or claims, these may be combined, and inclusion in different examples or claims does not imply that a combination of features is not feasible and / or advantageous.

[0378] The following claims are hereby incorporated by reference into the Detailed Description, with each claim standing on its own as a separate embodiment of this disclosure.

Claims

1. A lateral flow assay device comprising: a conjugate pad containing a conjugate corresponding to a target analyte in a biological sample, said conjugate being labeled with an enzyme; 1. A porous medium comprising a first zone and a second zone, the first zone comprises at least one of an immobilized antigen corresponding to the target analyte or an immobilized antibody corresponding to the target analyte; the second zone is laterally displaced from the first zone along a longitudinal axis of the lateral flow assay device; a porous medium that allows the flow of the biological sample, the conjugate with the enzyme, and a buffer solution to propagate along the porous medium; and a first electrode in contact with the porous medium in the first zone; a second electrode in contact with the porous medium in the second zone, wherein the first electrode and the second electrode detect an electrical signal when the target analyte is present in the biological sample and the enzyme reacts with the buffer; and a flow arrester that, after initiation of flow of the biological sample over the porous medium, obstructs the flow rate over the porous medium toward an absorbent pad when the flow arrester moves from a first position to a second position; and A lateral flow assay device comprising:

2. The absorbent pad is coupled to the porous medium, and the flow arrester is for at least one of compressing or shearing the porous medium and for at least one of reducing or stopping the flow rate toward the absorbent pad; The flow arrester includes a switch, the switch being movable from the first position to the second position to at least one of compress or shear the porous medium. The lateral flow assay device of claim 1 .

3. 3. The lateral flow assay device of claim 2, wherein movement of the switch to the second position causes the first electrode and the second electrode to contact the porous medium.

4. 4. The lateral flow assay device of claim 2 or claim 3, wherein the switch is at a first distance from the porous medium in the first position and at a second distance from the porous medium in the second position, the second distance being shorter than the first distance.

5. The lateral flow assay device of any one of claims 2 to 4, further comprising a circuit board, wherein the first electrode and the second electrode are coupled to the circuit board, and the switch moves at least a portion of the circuit board to bring it into proximity with the porous medium.

6. The lateral flow assay device of claim 5 , wherein the circuit board is pivotable, and when the switch moves, the switch causes the circuit board to pivot.

7. The lateral flow assay device according to any one of claims 2 to 6, wherein the flow arrester includes a first flow arrester and a second flow arrester.

8. the first flow arrestor is for at least one of compressing or shearing the porous medium in the first zone, and the second flow arrestor is for at least one of compressing or shearing the porous medium in the second zone; the first electrode and the second electrode are positioned between the first flow arrestor and the second flow arrestor; The lateral flow assay device according to claim 7.

9. The lateral flow assay device of any one of claims 1 to 8, wherein the flow arrester comprises a chemical that is adapted to form a barrier when wetted.

10. The lateral flow assay device of any one of claims 1 to 9, further comprising an antenna in a circuit with the first electrode and the second electrode, the antenna transmitting a radio signal representing the electrical signal to an external device.

11. an antenna in a circuit comprising the first electrode and the second electrode, the antenna being for receiving a power signal from an external device; a sensor that measures at least one of a voltage or a current between the first electrode and the second electrode, the sensor being operable based on the power supply signal, and the at least one of the voltage or the current being the electrical signal; a processor operable based on the power supply signal, comparing the at least one of the voltage or the current to a threshold; identifying the target analyte as present in the biological sample if the at least one of the voltage or the current is above the threshold; the antenna wirelessly transmits the results to the external device; and The lateral flow assay device according to any one of claims 1 to 10, further comprising:

12. The lateral flow assay device according to any one of claims 1 to 11, wherein the electrical signal is generated by an enzymatic reaction.

13. The lateral flow assay device according to any one of claims 1 to 12, wherein the lateral flow assay device is battery-less.

14. The lateral flow assay device, The lateral flow assay device of any one of claims 1 to 13, further comprising a switch that moves the flow arrester from the first position to the second position, the flow arrester shearing the porous medium to at least one of reduce or stop the flow of liquid toward the absorbent pad.

15. the switch is movable between the first position and the second position to at least one of compress or shear the porous medium; While the switch is in the second position, the switch causes the first electrode and the second electrode to contact the porous medium. The lateral flow assay device of claim 14.

16. 16. The lateral flow assay device of claim 15, wherein the switch is positioned a first distance from the porous medium in the first position and a second distance from the porous medium in the second position, the second distance being shorter than the first distance.

17. The lateral flow assay device of any one of claims 14 to 16, further comprising a reservoir, the reservoir containing a buffer solution, and the switch causing the reservoir to release the buffer solution onto the porous medium.

18. The lateral flow assay device according to any one of claims 14 to 17, wherein the flow arrester is for shearing the porous medium by cutting a portion of the depth of the porous medium.

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