A device for digital readout of lateral flow assays

Abstract

A device for receiving a digital reader and a lateral flow assay (LFA) cartridge, as well as a system incorporating the same, is provided. An embodiment of the device includes a body having a frame configured to receive the digital reader, and a base plate having one or more LFA cartridge receiving locations for positioning one or more LFA cartridges in a fixed orientation relative to a planar space defined by the frame. A method for using the device to read a result indicating the presence or absence of an analyte in a sample is also provided.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Patent Application No. 62 / 936,279, filed November 15, 2019, which is incorporated herein by reference in its entirety.

[0002] Introduction Sampling and testing of biological specimens is commonly used to evaluate humans, animals, and plants for any number of biochemical or physiological conditions, as well as to determine the general health of an organism. For example, sampling and testing of human bodily fluids is often performed for point-of-care testing ("POCT"). POCT is defined as medical testing at or near the point of patient care. The driving idea behind POCT is to conveniently and immediately deliver the test to the patient. This increases the likelihood of faster acceptance of the results by the patient, physician, and care team, which allows for immediate clinical management decisions to be made. Examples of POCT include, but are not limited to, blood glucose testing, hormone testing, cardiopulmonary, gastrointestinal, urological, dermatological, neurological, pediatric, surgical, public health, bioterrorism, food safety, veterinary and plant pathology testing, metabolic testing (e.g., thyroid stimulating hormone), blood gas and electrolyte analysis, rapid clotting testing, rapid cardiac marker diagnostics, drug abuse screening, urinalysis, pregnancy testing, fecal occult blood analysis, food pathogen screening, complete blood count ("CBC"), hemoglobin diagnostics, infectious disease testing, cholesterol screening cancer testing (e.g., PSA), hormone testing (hCG, LH, FSH), cardiac (troponin), pulmonary, gastrointestinal (e.g., H. pylori antibodies), urological, dermatological, neurological, pediatric, surgical, and public health (Ebola, cholera, HIV), and combinations thereof.

[0003] One testing method often used for POCT and more conventional testing involves the use of lateral flow chromatography immunoassay cassettes. Lateral flow chromatography immunoassay cassettes can be used to easily and quickly obtain a variety of qualitative results related to several biochemical and physiological conditions and disease states of an individual. These types of tests require the end user to simply add a sample to the cassette and then observe the results a few minutes later. Such rapid and easy-to-use tests are very popular in both professional and consumer markets because of their user-friendliness. Such tests are also very popular in areas where there is limited access to trained medical professionals or limited access to adequate medical facilities (e.g., poor areas, developing countries, war zones, etc.).

[0004] Lateral flow chromatography immunoassay methods and cartridges have been described extensively. See, for example, U.S. Patent No. 4,956,302 to Gordon and Pugh; WO 90 / 06511 to H. Buck et al.; U.S. Patent No. 6,764,825 to T. Wang; U.S. Patent No. 5,008,080 to W. Brown et al.; U.S. Patent No. 6,183,972 to Kuo and Meritt, EP 00987551 A3. Such assays involve the detection and determination of analytes that are members of a specific binding pair consisting of a ligand and a receptor. The ligand and receptor are related in that the receptor specifically binds to the ligand and can distinguish the specific ligand(s) from other sample components with similar characteristics. Immunological assays involving reactions between antibodies and antigens are one such example of specific binding assays. Other examples include DNA and RNA hybridization and binding reactions involving hormone and other biological receptors. One well-known commercial embodiment of this technology is the Clearblue One-Step Pregnancy Test. The terms "cartridge" and "cassette" are used interchangeably herein.

[0005] Lateral flow chromatography immunoassay test cassettes have several desirable features, including their ease of use and broad applicability to a variety of analytes. Similarly, immunoassay procedures that can be performed on test strips and administered on-site or at other locations where medical testing laboratories are not readily available, have provided significant benefits in disease diagnosis and control. However, currently, such lateral flow chromatography immunoassay tests are generally only capable of providing qualitative results. That is, currently available lateral flow chromatography immunoassay test cassettes and cassette reader devices are particularly suitable for informing practitioners whether one or more test substances are present in a sample above a given detection limit, but they are inadequate for providing quantitative results. There is a continuing need in the art for devices and methods that combine the ease of use features of lateral flow chromatography immunoassay tests with systems designed to provide quantitative results. Such devices and methods may, for example, enable physicians to diagnose various conditions at the point of care (e.g., chairside, or essentially anywhere in the world) without being tied to a medical facility or laboratory. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Pat. No. 4,956,302 [Patent Document 2] International Publication No. 90 / 006511 [Patent Document 3] U.S. Patent No. 6,764,825 [Patent Document 4] U.S. Patent No. 5,008,080 [Patent Document 5] U.S. Patent No. 6,183,972 [Patent Document 6] European Patent Application Publication No. 00987551 Summary of the Invention

[0007] A device for receiving a digital reader and a lateral flow assay (LFA) cartridge, as well as a system incorporating the same, is provided. An embodiment of the device includes a body having a frame configured to receive the digital reader, and a base plate having one or more LFA cartridge receiving locations for positioning one or more LFA cartridges in a fixed orientation relative to a planar space defined by the frame. A method for using the device to read a result indicative of the presence or absence of an analyte in a sample is also provided. [Brief description of the drawings]

[0008] [Figure 1] 1 illustrates one embodiment of a device having a body for receiving a digital reader and a base for receiving a lateral flow assay cartridge. [Figure 2A] 1 illustrates an overhead view of one embodiment of a lateral flow assay cartridge. [Figure 2B] FIG. 1 illustrates a side view of one embodiment of a lateral flow assay cartridge positioned relative to a digital reader. [Diagram 3] 1 illustrates a perspective view of one embodiment of a subject device. [Figure 4] 1 illustrates a first end view of one embodiment of the subject device. [Diagram 5] 1 illustrates an overhead view of one embodiment of the subject device. [Figure 6] 1 illustrates a side view of one embodiment of a subject device. [Figure 7] 1 illustrates a bottom view of one embodiment of the subject device. [Figure 8] 1 illustrates a second end view of one embodiment of the subject device. [Figure 9A] 1 illustrates one embodiment of a lateral flow assay cartridge positioned in an orientation relative to a surface of a digital reader. [Figure 9B]1 illustrates one embodiment of a lateral flow assay cartridge positioned in an orientation relative to a surface of a digital reader. [Figure 9C] 1 illustrates one embodiment of a lateral flow assay cartridge positioned in an orientation relative to a surface of a digital reader. [Figure 10A] 1 illustrates an overhead view of one embodiment of a base plate housing a lateral flow assay cartridge. [Figure 10B] 1 illustrates one embodiment of a receiving portion of a base plate. [Figure 11] 1 illustrates the perpendicular angle formed between the frame of the body of the subject device and the support surface of the receiving portion of the base plate. [Figure 12] 1 illustrates the horizontal angle formed between the frame of the body of the device and the support surface of the receiving portion of the base plate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A device for receiving a digital reader and a lateral flow assay (LFA) cartridge, as well as a system incorporating the same, is provided. An embodiment of the device includes a body having a frame configured to receive the digital reader, and a base plate having one or more LFA cartridge receiving locations for holding one or more LFA cartridges in a fixed orientation relative to a planar space defined by the frame. A method for using the device to read a result indicative of the presence or absence of an analyte in a sample is also provided.

[0010] Before exemplary embodiments of the invention are described, it is to be understood that the invention is not limited to the particular embodiments described, as such may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the invention will be limited only by the appended claims.

[0011] Where a range of values ​​is provided, it is to be understood that each intervening value between the upper and lower limits of that range is also specifically disclosed to the tenth of the unit of the lower limit, unless the context dictates otherwise. Each smaller range between any stated or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may be independently included or excluded in the range, and each range in which either, neither, or both limits are included in the smaller range is also encompassed within the invention, subject to any specifically excluded limits in the stated range. Where a stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included within the invention.

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, some potential exemplary methods and materials may be described herein. Any and all publications mentioned herein are incorporated by reference to disclose and describe the methods and / or materials for which the publications are cited. In case of conflict, it should be understood that the present disclosure supersedes any disclosure of the incorporated publication.

[0013] It should be noted that as used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to an "LFA cartridge" includes a plurality of LFA cartridges, and so forth.

[0014] It is further noted that the claims may be drafted to exclude elements that may be optional. Accordingly, this specification is intended to serve as a predicate basis for using exclusive terminology, such as "solely," "only," or "negative" limitations in connection with the recitation of claim elements.

[0015] The publications discussed herein are provided solely for their disclosure prior to the filing date of this application. Nothing herein should be construed as an admission that the present invention is not entitled to antedate such publications by virtue of prior invention. Further, the publication dates provided may differ from the actual publication dates, which may need to be independently confirmed. To the extent that such publications may provide definitions of terms that contradict the explicit or implicit definitions of the present disclosure, the definitions of the present disclosure shall control.

[0016] As will be apparent to those skilled in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has distinct components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the invention. Any recited method can be carried out in the order of events recited or in any other order which is logically possible.

[0017] definition To facilitate the understanding of the present technology, several terms and phrases are defined below. Additional definitions are set forth throughout the detailed description.

[0018] Throughout this specification and claims, unless the context clearly indicates otherwise, the following terms take on the meanings expressly associated therewith. As used herein, the phrase "in one embodiment" does not necessarily refer to the same embodiment, but may. Additionally, as used herein, the term "in another embodiment" does not necessarily refer to different embodiments, but may. Thus, as described below, various embodiments of the invention can be readily combined without departing from the scope or spirit of the invention.

[0019] Additionally, as used herein, the term "or" is an inclusive "or" operator and is equivalent to the term "and / or" unless the context clearly dictates otherwise. The term "based on" is not exclusive and allows for based on additional unrecited factors unless the context clearly dictates otherwise. The meaning of "in" includes "in" and "on."

[0020] As used herein, the terms "about," "approximately," "substantially," and "significantly" will be understood by those of ordinary skill in the art and will vary to some extent depending on the context in which they are used. If there are uses of these terms that are not clear to persons of ordinary skill in the art given the context in which they are used, "about" and "approximately" will mean plus or minus 10% or less of the particular term, and "substantially" and "significantly" will mean plus or minus greater than 10% of the particular term.

[0021] As used herein, the disclosure of a range includes the disclosure of all values ​​within the entire range and further divided ranges, including the endpoints and subranges given for the range.

[0022] As used herein, the suffix "-free" refers to an embodiment of a technology that omits a feature of the base root of the word to which "-free" is added. That is, the term "X-free" as used herein means "without X," where X is the feature of the technology that is omitted in the "X-free" technology. For example, a "calcium-free" composition does not contain calcium, a "mixing-free" method does not include a mixing step, etc.

[0023] Terms such as "first", "second", "third" and the like may be used herein to describe various steps, elements, compositions, components, regions, layers, and / or sections, but these steps, elements, compositions, components, regions, layers, and / or sections should not be limited by these terms unless otherwise indicated. These terms are used to distinguish one step, element, composition, component, region, layer, and / or section from another step, element, composition, component, region, layer, and / or section. As used herein, terms such as "first", "second", and other numerical terms do not imply an order or sequence unless clearly indicated by the context. Thus, a first step, element, composition, component, region, layer, or section discussed herein may be referred to as a second step, element, composition, component, region, layer, or section without departing from the art.

[0024] As used herein, the words "presence" or "absence" (or, alternatively, "present" or "absent") are used in a relative sense to describe the amount or level of a particular entity (e.g., an analyte). For example, when an analyte is said to be "present" in a test sample, it means that the level or amount of the analyte is above a predetermined threshold; conversely, when an analyte is said to be "absent" in a test sample, it means that the level or amount of the analyte is below a predetermined threshold. The predetermined threshold may be a threshold for detectability associated with a particular test used to detect the analyte or any other threshold. When an analyte is "detected" in a sample, the analyte is "present" in the sample, and when the analyte is "not detected", the analyte is "absent" in the sample. Furthermore, a sample in which an analyte is "detected" or in which the analyte is "present" is a sample that is "positive" for the analyte. A sample in which an analyte is "not detected" or in which the analyte is "absent" is a sample that is "negative" for the analyte.

[0025] As used herein, "increase" or "decrease" refers to a detectable (e.g., measured) positive or negative change, respectively, of a variable relative to a previously measured value, relative to a pre-established value, and / or relative to a standard control value. An increase is a positive change, preferably of at least 10%, more preferably 50%, even more preferably 2-fold, even more preferably at least 5-fold, and most preferably at least 10-fold, compared to a previously measured, pre-established, and / or standard control value of a variable. Similarly, a decrease is a negative change, preferably of at least 10%, more preferably 50%, even more preferably at least 80%, and most preferably at least 90% of a previously measured, pre-established, and / or standard control value of a variable. Other terms indicating a quantitative change or difference, such as "more" or "less," are used herein in the same format as above.

[0026] As used herein, a "system" refers to multiple real and / or abstract components that operate together for a common purpose. In some embodiments, a "system" is an integrated collection of hardware and / or software components. In some embodiments, each component of a system interacts with and / or is associated with one or more other components. In some embodiments, a system refers to a combination of components and software for controlling and directing a methodology.

[0027] As used herein, the term "analyte" refers to a compound or composition to be detected and / or measured. An analyte may be measured, for example, by specific binding to a binding agent (e.g., a ligand, receptor, enzyme, antibody, antigen, aptamer, or antibody mimetic). In some embodiments, the analyte is a protein or nucleic acid. In some embodiments, the analyte is an antigen, antibody, and / or receptor. In some embodiments, the analyte is a fragment of an antigen, antibody, and / or receptor. In some embodiments, the analyte is an analyte analog or analyte derivative (e.g., an analyte altered by chemical or biological methods). In some embodiments, the analyte is an epitope.

[0028] In some embodiments, the term "analyte" refers to proteins and / or nucleic acids from a pathogen, such as a viral, bacterial, fungal, or parasitic pathogen. In some embodiments, the term "analyte" refers to antibodies against such pathogens.

[0029] In some embodiments, the term "analyte" refers to a protein and / or a nucleic acid from the SARS-CoV-2 virus. In some embodiments, the analyte is a fragment and / or an epitope of a protein and / or a nucleic acid from the SARS-CoV-2 virus.

[0030] As used herein, the term "antibody" refers to immunoglobulins, immunoglobulin derivatives, and / or immunoglobulin fragments. An antibody contains areas on its surface or within a cavity that specifically bind to a particular spatial and / or polar organization of another molecule. Antibodies may be monoclonal or polyclonal and may be prepared by techniques well known in the art, such as, for example, immunization of a host and collection of serum or hybrid cell line techniques. Thus, the term "antibody" refers to immunoglobulins, derivatives thereof that maintain specific binding ability, as well as proteins having binding domains that are homologous or substantially and / or effectively homologous to immunoglobulin binding domains. These proteins may be derived from natural sources or may be partially or fully synthetically produced. An antibody may be a member of any immunoglobulin class, including any of the human classes: IgG, IgM, IgA, IgD, and IgE. The basic antibody structural unit is known to comprise a tetramer. Each tetramer is composed of two identical pairs of polypeptide chains, each pair having one "light" (about 25 kDa) and one "heavy" chain (about 50-70 kDa). The amino-terminal portion of each chain contains a variable region of about 100-110 or more amino acids primarily responsible for antigen recognition. The carboxy-terminal portion of each chain defines a constant region primarily responsible for effector function. Light chains are classified as either kappa or lambda. Heavy chains are classified as gamma, mu, alpha, delta, or epsilon, and antibody isotypes are defined as IgG, IgM, IgA, IgD, or IgE, respectively. Within the light and heavy chains, the variable and constant regions are joined by a "J" region of about 12 or more amino acids, with the heavy chain also containing a "D" region of about 10 or more amino acids. (See generally, Fundamental Immunology (see, e.g., Paul, Fundamental Immunology, 3rd Ed., 1993, Raven Press, New York). The variable regions of each light / heavy chain pair form the antibody binding site. All chains exhibit the same general structure of relatively conserved framework regions (FR) joined by three hypervariable regions, also called complementary determining regions or CDRs.The CDRs from the two chains of each pair are aligned by the framework regions, enabling binding to a specific epitope. The CDR and FR residues are described according to the standard sequence definition of Kabat et al. (5th ed., 1991) Sequences of Proteins of Immunological Interest (National Institutes of Health publication 91-3242, incorporated herein by reference). Alternative structural definitions have been proposed by Chothia et al. (1987) J. Mol. Biol. 196:901-917, (1989) Nature 342:878-883; and (1989) J. Mol. Biol. 186:651-663, each of which is incorporated herein by reference.

[0031] As used herein, the term "antibody fragment" refers to any derivative of an antibody that contains an amino acid sequence that is less than the full-length antibody amino acid sequence. In exemplary embodiments, an antibody fragment retains at least a substantial portion of the full-length antibody's specific binding ability. Examples of antibody fragments include Fab, Fab', F(ab') 2 Antibody fragments include, but are not limited to, scFv, Fv, dsFv diabody, and Fd fragments. Antibody fragments may be produced by any means. For example, antibody fragments may be enzymatically or chemically produced by fragmentation of an intact antibody, may be recombinantly produced from a gene encoding a partial antibody sequence, or may be wholly or partially synthetically produced. For example, in some embodiments, the term Fab fragment may refer to the binding fragment resulting from papain cleavage of an intact antibody, and includes Fab' and F(ab') fragments. 2The term "Fab" may refer to a binding fragment of an intact antibody generated by pepsin cleavage. As used herein, the term "Fab" is used generally to refer to a double-chain binding fragment of an intact antibody having at least substantially complete light and heavy chain variable domains sufficient for antigen-specific binding, and a portion of the light and heavy chain constant regions sufficient to maintain the association of the light and heavy chains. Typically, a Fab fragment is formed by complexing a full-length or substantially full-length light chain with a heavy chain that includes a variable domain and at least the CH1 domain of the constant region. An antibody fragment may optionally be a single-chain antibody fragment. Alternatively, the fragment may include multiple chains linked together, for example, by disulfide bonds. The fragment may also optionally be a multimolecular complex. A functional antibody fragment will typically include at least about 50 amino acids, more typically at least about 200 amino acids.

[0032] As used herein, the terms "specifically bind to" or "specifically immunoreact with", for example when referring to an antibody, antibody fragment, antigen, or other binding moiety, refer to a binding reaction that determines the presence of a target analyte in the presence of a heterogeneous population of proteins and / or other biologies. Thus, under specified assay conditions, a particular binding moiety will preferentially bind to a particular target analyte and will not bind in significant amounts to other components present in the test sample. Specific binding to a target antigen under such conditions may require a binding moiety that is selected for its specificity for a particular target analyte. A variety of immunoassay formats can be used to select antibodies that specifically immunoreact with a particular protein. For example, solid-phase ELISA immunoassays are routinely used to select monoclonal antibodies that specifically immunoreact with an antigen. For a description of immunoassay formats and conditions that can be used to determine specific immunoreactivity, see Harlow and Lane (1988) Antibodies, A Laboratory Manual, Cold Spring Harbor Publications, New York. Typically, a specific or selective reaction is at least twice the background signal or noise, and more typically 10 to 100 times more than background. Specific binding between an antibody or other binding agent and an antigen is generally at least 10 6 M -1 Preferred binding agents have a binding affinity of at least about 10 7 M -1 , and preferably 10 8 M -1 ~10 9 M -1 or 10 10 M -1 It binds with an affinity of

[0033] As used herein, the term "epitope" refers to an antigenic determinant capable of specific binding to an antibody. Epitopes usually comprise chemically active surface groups of molecular moieties, e.g., amino acids or sugar side chains, and usually have specific three-dimensional structural characteristics and / or specific charge characteristics. Conformational and non-conformational epitopes are distinguished in that the binding to the former but not the latter is lost in the presence of denaturing solvents. Epitopes can comprise non-contiguous amino acids as well as contiguous amino acids.

[0034] As used herein, the term "sample" refers to any sample that contains or is suspected to contain an analyte. Thus, the term "sample" refers to a material that is tested for the presence or amount of an analyte, e.g., a pathogen, or a part or component thereof. Preferably, the sample is a fluid sample, preferably a liquid sample. For example, the sample may be a bodily fluid, such as blood, serum, plasma, ocular fluid, urine, mucus, semen, nasopharyngeal swab, throat swab, tears, sweat, or saliva. Viscous liquid, semi-solid, or solid samples may be used to create liquid solutions, eluates, suspensions, or extracts that may serve as samples. For example, a throat or genital swab may be suspended in a liquid solution to create a sample.

[0035] As used herein, the term "test strip" may include one or more water-absorbent or non-water-absorbent materials. When a test strip includes two or more materials, 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, for example, filter paper overlaid on nitrocellulose. Alternatively or additionally, the test strip may include a region containing one or more materials followed by a region containing one or more different materials. In this case, the regions are in fluid communication and may or may not overlap each other. Suitable materials for test strips include, but are not limited to, materials derived from cellulose, such as filter paper, chromatography paper, nitrocellulose, and cellulose acetate, as well as materials made from glass fiber, nylon, Dacron, PVC, polyacrylamide, cross-linked dextran, agarose, polyacrylate, ceramic materials, and the like. The material(s) of the test strip may optionally be treated to modify their capillary flow properties or the properties of the applied sample. For example, the sample application area of ​​a test strip may be treated with a buffer to correct the pH, salt concentration, or specific gravity of the applied sample to optimize testing conditions.

[0036] The material(s) may be a unitary structure, such as a sheet cut into strips, or may be 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 may also be a sheet with lanes thereon, which can be spotted to induce lane formation, and separate assays may be performed within each lane. The material may have a rectangular, circular, oval, triangular, or other shape, provided that there is at least one direction of traversal of the test solution by capillary water movement. Other traversal directions may occur, such as an oval or circular piece in contact with the test solution in the center. However, the primary consideration is that there is at least one direction of flow to a given location.

[0037] The support of a test strip where a support is desired or required is usually water-insoluble, often non-porous, rigid, but may be elastic, usually hydrophobic, porous, and usually the same length and width as the strip, but may be larger or smaller. The support material may be transparent, and may be on the side of the test strip that can be viewed by the user, such that when the test device of the present technology is assembled, the transparent support material forms a protective layer on the test strip that may be exposed to the external environment, such as by an aperture in the front of the test device. A wide variety of non-moving and non-moving materials, both natural and synthetic, and combinations thereof may be employed, provided only that the support does not interfere with the capillary action of the material(s) or non-specifically bind to the assay components or interfere with the signal generating 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 elastic support may be made from polyurethane, neoprene, latex, silicone rubber, and the like.

[0038] As used herein, the term "control zone" or "control line" refers to an area of ​​a test strip where a label can be observed to shift location, appear, change color, or disappear to indicate that the assay has been performed correctly. Detection or observation of a control zone (e.g., control line) can be performed by any convenient means, including, but not limited to, for example, visually, fluorescently, by reflectance, radiographically, etc., depending on the particular selection of the label. As explained, a label may or may not be applied directly to the control zone, depending on the design of the control used.

[0039] As used herein, the term "label" refers to any molecule attached to a specific binding member capable of generating a detectable signal. In the present invention, the label may be inert, may provide a signal by concentrating in a detection zone, may function only as a binding site for a member of a signal producing system, or may spontaneously generate a detectable signal, or may generate a detectable signal in conjunction with a signal producing system. The label may be isotopic or nonisotopic. In some embodiments, the label comprises a gold colloid, a latex bead, a dye, a fluorescent moiety, or other detectable entity.

[0040] "Proximal end" refers to the end of a testing device or test strip that contains the sample application aperture of a testing device and / or the sample application zone of a test strip.

[0041] As used herein, the term "reagent zone" refers to an area of ​​a test strip where a reagent is provided. The reagent zone may be on a reagent pad, a separate segment of bibulous or non-bibulous material contained on the test strip, or may be an area of ​​bibulous or non-bibulous material of the test strip that also includes other zones, such as an analyte detection zone. The reagent zone may carry a detectable label, which may be a direct or indirect label. Preferably, the reagent is provided in a form that is immobile in the dry state and mobile in the wet state. The reagent may be a chemical or compound that contributes to the function of the test strip assay, such as a specific binding member, an analyte or analyte analogue, an enzyme, a substrate, an indicator, a component of a signal producing system, a buffer, a reducing agent, a chelating agent, a surfactant, etc.

[0042] As used herein, the term "sample application aperture" refers to the portion of a testing device where an opening in the testing device provides access to the sample application zone of a test strip.

[0043] As used herein, the term "sample application zone" is the portion of a test strip where a sample is applied. In some embodiments, a "sample pad" comprises a sample application zone.

[0044] As used herein, the term "specific binding member" refers to one of two different molecules that have an area on the surface or in a cavity that specifically binds, thereby being defined as complementary to a particular spatial and polar organization of the other second molecule. The members of a specific binding pair are referred to as a ligand and a receptor (antiligand). These can usually be members of an immunological pair, such as an antigen-antibody, but other specific binding pairs, such as biotin-avidin, hormone-hormone receptor, nucleic acid duplexes, IgG-protein A, DNA-DNA, DNA-RNA, etc., are included in the definition, although they are not immunological pairs. In the case of a binding pair such as avidin-biotin, the reagent can be labeled with one member of the pair, and the detection zone can contain the other member of the pair in a capture type assay. Other common types of assays using avidin-biotin pairs or binding pairs of this type are known in the art. Antibodies (e.g., labeled antibodies) can be used as reagents for the detection of antigens that bind or specifically bind to such antibodies. Antigens or epitopes (eg, labeled antigens) can be used as reagents for the detection of antibodies which bind or specifically bind to such antigens or epitopes.

[0045] As used herein, the term "test result zone" is an area of ​​a test strip that provides a detectable signal indicative of the presence of an analyte. The test result zone may contain an immobilized binding reagent specific for the analyte ("specific binding member") and / or an enzyme that reacts with the analyte. The test result zone may include one or more analyte detection zones, e.g., "test lines." Other substances that may enable or enhance detection of the analyte, such as substrates, buffers, salts, etc., may also be provided in the test result zone. One or more members of a signal producing system may be directly or indirectly bound to the detection zone. The test result zone may optionally include one or more control zones (e.g., "control lines") that provide an indication that the test is being performed properly.

[0046] The term "identical" or percent "identity" in the context of two or more nucleic acid or polypeptide sequences refers to two or more sequences or subsequences that are the same or have a certain percentage of nucleotides or amino acid residues that are the same when compared and aligned for maximum correspondence as determined using one of the sequence comparison algorithms below or by visual inspection. The phrase "substantially identical" in the context of two nucleic acids refers to two or more sequences or subsequences that have at least 80%, preferably 85%, and most preferably 90-95% nucleotide identity when compared and aligned for maximum correspondence as determined using one of the sequence comparison algorithms below or by visual inspection. With respect to amino acid sequences, "substantially identical" refers to two or more sequences or subsequences that have at least 60% identity, preferably 75% identity, and more preferably 90-95% identity when compared and aligned for maximum correspondence as determined using one of the sequence comparison algorithms below or by visual inspection. Preferably, the substantial identity exists over a region of the nucleic acid or amino acid sequence that is at least about 10 residues in length, more preferably over a region of at least about 20 residues, and most preferably the sequences are substantially identical over a region of at least about 100 residues. In the most preferred embodiments, the sequences are substantially identical over the entire length of a particular region (e.g., the coding region).

[0047] For sequence comparison, typically, one sequence acts as a reference sequence to which the test sequence is compared.When using sequence comparison algorithm, the test and reference sequences are input into a computer, subsequence coordinates are designated as necessary, and sequence algorithm program parameters are designated.The sequence comparison algorithm then calculates the percent sequence identity of the test sequence(s) to the reference sequence based on the designated program parameters. Optimal alignment of sequences for comparison can be determined, for example, by the local homology algorithm of Smith & Waterman, Adv. Appl. Math. 2:482 (1981), by the homology alignment algorithm of Needleman & Wunsch, J. Mol. Biol. 48:443 (1970), by the similarity search method of Pearson & Lipman, Proc. Nat'l. Acad. Sci. USA 85:2444 (1988), or by computer implementations of these algorithms (GAP, BESTFIT, FASTA, and TFASTA in the Wisconsin Genetics Software Package, Genetics Computer Group, 575 Science Dr., Madison, Wis.), or by visual inspection (see generally Current Protocols in Molecular Biology, FMAusubel et al., eds., Current Protocols, a joint venture between Greene Publishing Associates, Inc. and John Wiley & Sons, Inc., (1995 Supplement) (Ausubel).

[0048] Examples of algorithms suitable for determining percent sequence identity and sequence similarity are the BLAST and BLAST 2.0 algorithms described in Altschul et al. (1990) J. Mol. Biol. 215:403-410, and Altschuel et al. (1977) Nucleic Acids Res. 25:3389-3402, respectively. Software for performing BLAST analysis is publicly available through the National Center for Biotechnology Information (www.ncbi.nlm.nih.gov). This algorithm involves first identifying high-scoring sequence pairs (HSPs) by identifying short words of length W in the query sequence that match or meet some positive threshold score T when aligned with words of the same length in a database sequence. T is referred to as the neighborhood word threshold (Altschul et al., supra). These initial neighborhood word hits act as seeds to initiate searches to find longer HSPs that contain them. The word hits are then extended in both directions along each sequence as far as the cumulative alignment score can be increased. The cumulative score is calculated using, for nucleotide sequences, the parameters M (reward score for a pair of matching residues; always >0) and N (penalty score for mismatching residues; always <0). For amino acid sequences, a scoring matrix is ​​used to calculate the cumulative score. The extension of the word hits in each direction is stopped: when the cumulative alignment score falls by a quantity X from its maximum achieved value; when the cumulative score falls below zero due to the accumulation of one or more negative-scoring residue alignments; or when the end of either sequence is reached. The BLAST algorithm parameters W, T, and X determine the sensitivity and speed of the alignment. The BLASTN program (for nucleotide sequences) uses as defaults a wordlength (W) of 11, an expectation (E) of 10, M=5, N=-4, and a comparison of both strands.For amino acid sequences, the BLASTP program uses as defaults a wordlength (W) of 3, an expectation (E) of 10, and the BLOSUM62 scoring matrix (see Henikoff & Henikoff, Proc. Natl. Acad. Sci. USA 89:10915 (1989)).

[0049] A further indication that two nucleic acids or polypeptides are substantially identical is that the polypeptide encoded by the first nucleic acid is immunologically cross-reactive with the polypeptide encoded by the second nucleic acid, as described below. Thus, a polypeptide is typically substantially identical to a second polypeptide, e.g., the two peptides differ only by conservative substitutions. Another indication that two nucleic acid sequences are substantially identical is that the two molecules hybridize to each other under stringent conditions, as described below.

[0050] "Conservatively modified variants" of a particular polynucleotide sequence refer to those polynucleotides that encode identical or essentially identical amino acid sequences, or polynucleotides where the polynucleotide does not encode an amino acid sequence relative to an essentially identical sequence. Due to the degeneracy of the genetic code, a large number of functionally identical nucleic acids encode any given polypeptide. For example, the codons CGU, CGC, CGA, CGG, AGA, and AGG all encode the amino acid arginine. Thus, at all positions where arginine is specified by a codon, the codon can be altered to any of the corresponding codons described without altering the encoded polypeptide. Such nucleic acid variants are "silent substitutions" or "silent variants," which are one species of "conservatively modified variants." All polynucleotide sequences described herein that encode a polypeptide also describe all possible silent variants, unless otherwise noted. Thus, silent substitutions are an implicit feature of all nucleic acid sequences that encode amino acids. One of skill in the art will recognize that each codon in a nucleic acid (except AUG, which is usually the only codon for methionine, and UGG, which is the only codon for tryptophan) can be modified by standard techniques to obtain a functionally identical molecule. In some embodiments, the nucleotide sequence encoding the enzyme is preferably optimized for expression in the particular host cell (e.g., yeast, mammalian, plant, fungus, etc.) used to produce the enzyme.

[0051] Similarly, "conservative amino acid substitutions" of one or several amino acids in an amino acid sequence are easily identifiable as being substituted with different amino acids having very similar properties, and are very similar to a particular amino acid sequence, or to a particular nucleic acid sequence encoding the amino acids. Such conservatively substituted variants of any particular sequence are a feature of the present invention. Individual substitutions, deletions, or additions that alter, add, or delete a single amino acid or a small percentage of amino acids (typically less than 5%, more typically less than 1%) in the encoded sequence are "conservatively modified mutations", where the alteration results in the replacement of an amino acid with a chemically similar amino acid. Conservative substitution tables providing functionally similar amino acids are well known in the art. See, for example, Creighton (1984) Proteins, W.H. Freeman and Company.

[0052] device Described herein are devices, systems, and methods relating to a digital reader and a device for receiving a lateral flow assay (LFA) cartridge, various aspects of the device will now be described in more detail below.

[0053] Aspects of the device may include two modules: a body configured to receive a digital reader and a base plate configured to receive an LFA cartridge. In certain embodiments, the device may be used to digitally read the assay and / or control regions of the LFA cartridge.

[0054] The body of the device may have any suitable structure for receiving a digital reader. The body may include a wall enclosing a space, the wall having a top portion and a bottom portion. The wall may have any suitable dimensions. In some cases, the wall has a height in the range of 0.5 inches to 7 inches, such as, for example, 1 inch to 6 inches, 2 inches to 5 inches, or 3 inches to 4 inches. In some cases, the wall encloses a space having a length in the range of 3 inches to 10 inches, such as, for example, 4 inches to 9 inches, 5 inches to 8 inches, or 5 inches to 7 inches. In some cases, the wall encloses a space having a width in the range of 1 inch to 6 inches, such as, for example, 2 inches to 5 inches, 2 inches to 4 inches, or 3 inches to 4 inches. The body may further include a frame coupled to the top portion of the wall, the frame configured to receive a digital reader. The frame may have any suitable dimensions for receiving various digital readers, including, for example, smartphones, digital cameras, and the like. In some cases, the frame extends around the entire body of the digital reader, e.g., around the edges of the digital reader. In some cases, the frame extends around the entire body of the digital reader, but leaves the screen, power port, and / or on / off switch exposed. In some cases, the frame is sized to receive a portion of the body of the digital reader, e.g., half of the body of the digital reader. The body of the device may further include a mating structure defined by a bottom portion of the wall, the mating structure configured to removably couple to the base plate. The mating structure may have any suitable shape, e.g., a rectangular shape, a square shape, a circular shape, a triangular shape, a pentagonal shape, etc.

[0055] The base plate of the device may have any suitable structure for receiving one or more LFA cartridges, e.g., at least two LFA cartridges. The base plate may include a first surface and a second surface defining a space therebetween, the space including the first LFA cartridge receiving portion and / or the second LFA cartridge receiving portion therein. In some cases, the first LFA cartridge receiving portion includes a substantially planar first support surface that receives and holds the LFA cartridge in a releasable manner. In some cases, the second LFA cartridge receiving portion includes a substantially planar second support surface that receives and holds the LFA cartridge in a releasable manner. In some cases, the first support surface has a first fixed orientation and the second support surface has a second fixed orientation for optimizing detection of optically detectable markings (e.g., optically detectable lines, optically detectable bands) present on the LFA cartridge during use of the device. In some cases, the first and second fixed orientations are different. In some cases, the first and second fixed orientations are the same. In certain embodiments, the first surface includes a structure for coupling the base plate to the body, such as, for example, a protrusion that fits into a mating structure on the body. In some cases, at least a portion of the base plate is shaped to fit with a mating structure on the body. In some cases, at least one portion of the base plate can have any suitable shape, such as, for example, a rectangular shape, a square shape, a circular shape, a triangular shape, a pentagonal shape, etc. In some cases, the base plate has a triangular shape and includes at least three receiving portions in a triangular arrangement. In some cases, the base plate has a rectangular or square shape and includes at least four receiving portions in a rectangular or square arrangement. In some cases, the base plate has a pentagonal shape and includes at least five receiving portions in a pentagonal arrangement.

[0056] In some cases, the first support surface of the first LFA cartridge receiving portion is at a first fixed orientation with respect to a planar space defined by the frame of the body. In some cases, the first fixed orientation includes a first fixed horizontal angle with respect to the planar surface of the frame. As used herein, "horizontal angle" refers to an angle formed at the intersection between a laterally extending planar surface and the plane of the first support surface. In some cases, the first fixed horizontal angle is an angle caused by a tilt of a lateral edge of the first support surface of the receiving portion away from the planar surface defined by the frame such that a first longitudinal edge of the first support surface is farther away from the planar surface than a second longitudinal edge. In some cases, the first fixed horizontal angle, e.g., its positive or negative tilt, is determined by the precise position of the illumination source relative to the camera position. In some cases, the first fixed horizontal angle is in the range of +1 to +10 degrees, +2 to +8 degrees, or +3 to +6 degrees. In some cases, the first fixed horizontal angle ranges from -1 to -10 degrees, -2 to -8 degrees, or -3 to -6 degrees. As used herein, tilting away from the planar surface defined by the frame may be considered to generate a positive angle, and tilting towards the planar surface may be considered to generate a negative angle. In some cases, the first fixed orientation comprises a first fixed vertical angle with respect to the planar surface of the frame. As used herein, "vertical angle" refers to the angle formed at the intersection between the longitudinally extending planar surface and the plane of the first support surface. In some cases, the first fixed vertical angle is an angle caused by the tilt of a vertical edge of the first support surface of the receiving portion towards the planar surface of the frame such that the first lateral edge of the receiving portion is closer to the planar surface than the second lateral edge. In some cases, the first fixed vertical angle, e.g., its positive or negative tilt, is determined by the precise position of the illumination source relative to the camera position. In some cases, the first fixed vertical angle is in the range of -1 to -15 degrees, -3 to -12 degrees, or -5 to -10 degrees. In some cases, the first fixed vertical angle is in the range of +1 to +15 degrees, +3 to +12 degrees, or +5 to +10 degrees.In certain embodiments, the first fixed horizontal angle and / or the first fixed vertical angle results in a) less light being reflected directly into the camera lens and / or b) the most homogeneous intensity distribution of reflected light from the result area of ​​the LFA.

[0057] In some cases, the second support surface of the second LFA cartridge receiving portion is at a second fixed orientation with respect to the planar space defined by the frame of the body. In some cases, the second fixed orientation may be the same as the first fixed orientation and have the same fixed horizontal angle and fixed vertical angle as the first fixed orientation. In certain embodiments, the second fixed orientation may be the same as the first fixed orientation such that when the second support surface is positioned in front of a reader, e.g., a smartphone, the second support surface has the same orientation as the first support surface when positioned in front of a detector. In some cases, the second fixed orientation may be different from the first fixed orientation and have a different fixed horizontal angle and fixed vertical angle. In some cases, the second fixed orientation includes a second fixed horizontal angle with respect to the planar surface of the frame. In some cases, the second fixed horizontal angle, e.g., its positive or negative tilt, is determined by the precise position of the illumination source with respect to the camera position. In some cases, the second fixed horizontal angle is in the range of +1 to +10 degrees, +2 to +8 degrees, or +3 to +6 degrees. In some cases, the second fixed horizontal angle is in the range of -1 to -10 degrees, -2 to -8 degrees, or -3 to -6 degrees. In some cases, the second fixed orientation includes a second fixed vertical angle with respect to the planar surface of the frame. In some cases, the second fixed vertical angle, e.g., its positive or negative tilt, is determined by the precise position of the illumination source with respect to the camera position. In some cases, the second fixed vertical angle is in the range of -1 to -15 degrees, -3 to -12 degrees, or -5 to -10 degrees. In some cases, the second fixed vertical angle is in the range of +1 to +15 degrees, +3 to +12 degrees, or +5 to +10 degrees. In certain embodiments, the second fixed horizontal angle and / or the second fixed vertical angle results in a) less light being reflected directly into the camera lens and / or b) the most homogeneous intensity distribution of reflected light from the result area of ​​the LFA.

[0058] In certain embodiments, the receiving portions can have different sizes, for example, a first receiving portion can be larger such that it can releasably hold a first LFA cartridge having a larger size than a second LFA cartridge that can fit into the second receiving portion.

[0059] In some cases, the body and the base plate are coupled by a mating structure defined by the body and a protrusion of the base plate, as described above. In some cases, the orientation of the base plate relative to the body of the device may be adjustable. In some cases, the mating structure and at least a portion of the base plate have a shape with a line of symmetry such that the mating structure and the base plate may be coupled in at least two orientations by rotation of one of the mating structure and the base plate. In some cases, the rotation positions the first receiving portion in front of an imaging device of a digital reader carried on the body of the device. In some cases, the rotation positions the second receiving portion in front of an imaging device of a digital reader carried on the body of the device.

[0060] The device may be fabricated from any suitable material. In some cases, the device is fabricated from an opaque material, including but not limited to plastic, metal, wood, etc. In certain embodiments, the device is fabricated from a light absorbing material, including nanotubes, dark materials, including dark paint, plastic, paper, wood, etc. In some cases, the first surface of the base plate faces the interior of the device and comprises a light absorbing material.

[0061] The device may further include a threshold intensity line. The threshold intensity line may function as an internal intensity standard. The threshold intensity line may be used, for example, to flag false negative results. For example, if the threshold intensity line is not detected by the digital reader, the LFA cartridge may not be read or the LFA cartridge reading results may be discarded. In some embodiments, if the threshold intensity line is not detected by the digital reader, settings on the digital reader may be adjusted, for example, a flash function of the digital reader may be activated to increase illumination within the device, and / or the focal plane of the reader's camera may be changed. In some embodiments, if the threshold intensity line is not detected by the digital reader, the user may be instructed to clean the reader's camera lens. In some cases, the threshold intensity line may be used to calculate a validity score and distinguish between valid and invalid readings of the assay region.

[0062] In some cases, reading the threshold intensity line can be used to determine that a digital reader, such as a smartphone camera, is functioning properly or to identify a suitable reader for use with the device. In some cases, detection of the threshold intensity line is used to determine the validity of the assay results under various conditions (e.g., ambient light intensity, degree of contamination on optical surfaces, autofocus accuracy of the digital reader). In some cases, the device includes more than one threshold intensity line.

[0063] In some cases, the base plate of the device includes a threshold intensity line on a first surface and disposed adjacent to the first LFA cartridge receiving portion or the second LFA cartridge receiving portion. In some cases, the device includes a first threshold intensity line on the first surface of the base plate and disposed adjacent to the first LFA cartridge, and a second threshold intensity line on the first surface of the base plate and disposed adjacent to the second LFA cartridge. In some cases, the threshold intensity line is in the same plane as the assay area of ​​the LFA cartridge during image capture by the digital reader. In some cases, the threshold intensity line is in the same focal path as the assay area during image capture by the digital reader. In some cases, the threshold intensity line is in a different plane than the assay area during image capture by the digital reader.

[0064] In some cases, the threshold intensity line is present on a substantially planar solid support. The solid support may be positioned on a first surface of a base plate, for example, by adhering the solid support to the first surface. In some cases, the solid support may be inserted into a cavity created in the base plate, the cavity opening to the first surface. Solid support is used in its conventional sense to refer to a surface on which the threshold intensity line can be generated. The solid support may be configured as a substantially planar substrate. Suitable solid supports may have a variety of shapes, sizes, forms, and compositions, and may be derived from naturally occurring materials, synthetically modified naturally occurring materials, or synthetic materials. Non-limiting examples of suitable solid support materials include, but are not limited to, nitrocellulose, glass, silica, ceramics, Teflon, metals (e.g., gold, platinum, etc.), or other materials. Non-limiting examples of solid support materials include polymeric materials including, but not limited to, plastics (e.g., polytetrafluoroethylene, polypropylene, polystyrene, polycarbonate, and mixtures thereof, etc.), polysaccharides such as agarose and dextran, polyacrylamide, polystyrene, polyvinyl alcohol, copolymers of hydroxyethyl methacrylate and methyl methacrylate, etc. The solid support may be a homogeneous or composite structure of two or more different materials, e.g., the solid support includes a first base material coated on its surface with one or more additional different coating materials. In certain embodiments, the solid support is fabricated from a material having a reflective surface. In some cases, the solid support is a glass substrate. In some cases, the solid support includes a ceramic sheet. The solid support may be substantially flat. The solid support may be substantially circular, square, or rectangular in shape, or may have an irregular shape.

[0065] The threshold intensity line can be generated on the solid support by any suitable method. Non-limiting examples of means for generating the threshold intensity line include vapor deposition coating, scratching (e.g., with a steel or diamond needle), etching, photolithography, atomic layer deposition, laser scribing or etching, laser ablation, flexographic printing, and inkjet printing. The threshold intensity line can be a line of similar width to the signal line in a lateral flow assay. In some cases, the threshold intensity line has a width in the range of 0.1 mm to 2 mm, 0.5 mm to 1.5 mm, 0.8 mm to 1.2 mm.

[0066] The threshold intensity line may have a detection intensity that is close to a minimum detection intensity required to be visually readable by the naked eye. In some cases, the threshold intensity line has a reflection intensity that is less than the surface reflection intensity of the solid support. In some cases, the threshold intensity line has a reflection intensity that is at least 0.01-30%, at least 0.03-20%, or at least 0.05-15% lower than the surface reflection intensity of the solid support. In some cases, the threshold intensity line has a reflection intensity that is at least 0.1-10% lower than the surface reflection intensity of the solid support. In some cases, the device includes one or more threshold intensity lines, each of the threshold intensity lines having the same intensity. In some cases, the device includes one or more threshold intensity lines, each of the threshold intensity lines having a different intensity.

[0067] In some cases, a threshold intensity line is generated in a white pigmented ceramic sheet by scratching a straight line into the surface by using a steel or diamond needle applied with a defined force and at a defined location, resulting in at least 0.1% lower intensity in this line region compared to other regions when a digital image of both regions is taken with a reader, e.g., a smartphone.

[0068] In some cases, a threshold intensity line is generated in a glass substrate modified on the surface or in the internal body by applying a focused laser at a defined location, resulting in an intensity that is at least 0.1% lower or higher for this line region compared to other regions when digital images of both regions are taken with a reader, e.g., a smartphone.

[0069] In some cases, a threshold intensity line is generated in a glass substrate backed by a light color (e.g., white), obtaining a line deposited by metal vapor (using a mask to define the line location), and using the deposition time to determine the line intensity, resulting in at least 0.1% lower intensity in this line region compared to other regions when digital images of both regions are taken with a reader, e.g., a smartphone.

[0070] system The present disclosure also provides a system that finds use, for example, in reading lateral flow assay cartridges. The system includes a digital reader and a device for receiving an LFA cartridge, as described above.

[0071] In some cases, the system of the present disclosure includes one or more LFA cartridges. A typical LFA cartridge may include a housing that contains a test strip, e.g., a plastic strip or ceramic sheet laminated with a porous material that allows for lateral flow of liquid. The LFA cartridge may include a sample application area and an analysis area. In some cases, the LFA cartridge includes an area with an optically detectable assay result. In some cases, the one or more LFA cartridges include at least two LFA cartridges, at least three LFA cartridges, at least four LFA cartridges, at least five LFA cartridges, or at least six LFA cartridges.

[0072] In one type of LFA cartridge, the test strip is divided into four regions, which may be made of only one type of material or several types of materials (e.g., up to four different types of materials). The first region is for sample addition. It functions to remove viscous and particulate matter in the sample and also to condition the sample solution for reactions in the following domains. The second domain is a mobile phase with a color conjugate. The color conjugate may be made of a conjugate between a visible color marker (e.g., colored beads, colloidal gold, fluorescent dyes, etc.) and a detection antibody. The detection antibody may bind to a specific antigen in the sample (e.g., an analyte of interest or a positive control substance) and form an antigen-color conjugate complex. The third region of the LFA cartridge is a solid phase with an immobilized capture antibody. The capture antibody may bind the antigen of the antigen-color conjugate complex and form a capture antibody-antigen-color conjugate sandwich. The fourth region is for solution absorption. It continuously draws the sample solution towards it.

[0073] During testing, the sample added to the first region flows into the second region. If an antigen is present in the sample, it will bind to the color conjugate to form an antigen-color conjugate complex. This complex then migrates to the third region and binds the capture antibody, forming a capture antibody-antigen-color conjugate complex sandwich. Since the capture antibody is immobilized within the third region, the sandwich shows as a visible color signal or a fluorescent signal at the site of the capture antibody, depending on the type of dye. If no antigen is present in the sample, the sandwich cannot be formed and therefore no visible color signal can be seen in the third domain. This is the so-called non-competitive immunoassay or sandwich assay, where the amount of signal is directly proportional to the concentration of the analyte of interest in the sample.

[0074] In some cases, the analyte(s) of interest and the positive control may be detected on different target lines, respectively, using different reporters. The reporters on each of the different target lines may be the same or different. Examples of suitable reporters include, but are not limited to, visible and fluorescent dyes, latex beads, enzymes, gold nanoparticles, silver nanoparticles, quantum dots, and the like.

[0075] The lateral flow chromatography immunoassay cassette can also be adapted for competitive immunoassays. In competitive immunoassays, the analyte of interest in an unknown sample competes with a labeled analyte for binding to the antibody. In competitive assays, the labeled analyte can provide a known signal. In the assay, the amount of labeled analyte bound to the antibody is measured, and any reduction in the known signal is due to the presence of the analyte in the sample. That is, in this method, the response is inversely proportional to the concentration of the unknown analyte. This is because the greater the response, the less unknown antigen was available to compete with the labeled antigen.

[0076] Lateral flow chromatography immunoassay cassettes can be adapted to assay a number of different analyte types. For example, immunoassay cassettes are or may be adapted in the future for blood glucose testing, metabolic testing (e.g., thyroid stimulating hormone), blood gas and electrolyte analysis, rapid clotting testing, rapid cardiac marker diagnostics, drug of abuse screening, urinalysis, pregnancy testing, fecal occult blood analysis, food pathogen screening, complete blood count ("CBC"), hemoglobin diagnostics, infectious disease testing, cholesterol screening, hormone testing, cardiopulmonary, gastroenterology, urology, dermatology, neurology, pediatrics, pediatrics, surgery, public health, and veterinary and plant pathology testing, combinations thereof, and the like.

[0077] In some cases, when a sample is applied to the diffusion strip of a lateral flow chromatography assay cartridge, the liquid in the sample carries the analyte of interest in a flow direction through the diffusion strip to an analysis zone, where it can be captured by a capture ligand line. In some cases, the LFA cartridge includes a first capture ligand line for capturing a first analyte of interest. In some cases, the LFA cartridge includes a second capture ligand line for capturing a second analyte of interest. In some cases, the LFA cartridge includes first and second capture ligand lines with an amount of the analyte of interest or another material pre-bound to the diffusion strip of the lateral flow chromatography assay cartridge. The reporter can be a diffusible material that can bind to the capture ligand line in an amount proportional to the amount of bound ligand present in each line. In response to illumination by a light source, the reporter bound to each of the lines provides a signal that can be used to calculate a calibration curve and then determine the concentration of the analyte of interest in the sample.

[0078] In some cases, one or more LFA cartridges of the system include an assay area for generating an optically detectable assay result. In some cases, one or more LFA cartridges of the system include a positive control area in addition to the assay area for generating an optically detectable marking. In some cases, the assay area includes a positive control line for determining that the assay was performed correctly.

[0079] In some cases, the system includes a digital reader. Digital readers suitable for use with the subject device include, but are not limited to, smartphones, digital cameras, and the like. In some cases, the digital reader includes a computing device with an automatic camera, a light source, and a touch screen. In certain embodiments, the digital reader is a camera phone (e.g., an Apple brand iPhone). In certain embodiments, the digital reader can be essentially any camera phone or digital camera. In certain embodiments, the digital camera device is a camera phone or digital camera with on-board image processing capabilities and the ability to wirelessly communicate with a database.

[0080] In some cases, one or more embodiments of the present invention may be practiced in a mobile consumer computing device. A mobile consumer computing device, or more simply, a mobile consumer device, may be any of a wide range of computing devices designed or optimized for portability and personal use. Mobile consumer devices may take a variety of forms, from more traditional notebook and netbook computers to the emerging and rapidly growing market of handheld devices, including smartphones (e.g., APPLE IPHONE, ANDROID PHONE, WINDOWS PHONE, SYMBIAN PHONE), tablet computers (e.g., APPLE IPAD, ANDROID TABLET), gaming devices (e.g., NINTENDO or PLAYSTATION portable gaming devices, APPLE IPOD), multimedia devices (e.g., APPLE IPOD), and combinations thereof. Many of these devices may enable rich user interaction by including a combination of outputs, inputs, and other sensory devices, such as touch or pressure sensitive displays (e.g., using capacitive or resistive technologies), still and video cameras, Global Positioning System (GPS) receivers, magnetic compasses, gyroscopes, accelerometers, light sensors, proximity sensors, microphones, speakers, etc. These devices may also include various communication devices, such as combinations of cellular modems (e.g., Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA)), Wireless Fidelity (Wi-Fi) radios, Bluetooth radios, Near Field Communication (NFC) devices, etc. Many mobile consumer devices are expandable, allowing users to add new hardware and capabilities that are not present during the manufacture of the device. It will be appreciated that as the market for mobile consumer devices expands and develops, the capabilities of these devices will also expand to take advantage of new and improved user interaction and communication devices.The embodiments described herein are broad in scope and can take advantage of any future developments in the field of mobile consumer devices.

[0081] The digital reader may include or be in communication with a computer-readable medium. In some cases, the digital reader includes or is in communication with a computer-readable medium that includes instructions that cause a processor to: detect a threshold intensity line and indicate successful detection of the threshold intensity line.

[0082] In some cases, the digital reader comprises or is in communication with a computer readable medium containing instructions that cause a processor to analyze an image containing an optically detectable assay result captured by the digital reader and indicate the presence or absence of an analyte in a sample assayed by the LFA cartridge. In some cases, the computer readable medium contains an algorithm that converts the visual readout from the interaction of the at least one analyte of interest with the at least one capture ligand into a numerical value related to the presence or amount of the at least one analyte of interest present in the sample.

[0083] In some cases, the computer readable medium includes instructions that cause the processor to determine whether a threshold intensity line is detected to determine validity of the optically detectable assay result. In some cases, the computer readable medium includes instructions that cause the processor to compare a signal detected from the optically detectable assay result to a signal from the threshold intensity line to determine validity of the optically detectable assay result. In some cases, the computer readable medium includes instructions that cause the processor to execute an algorithm that provides an indication of an error when the threshold intensity line is not detected.

[0084] In one embodiment, the digital reader further includes or is in communication with a computer readable medium containing instructions that cause the processor to at least one of: (1) communicate with an electronic medical record system via a wireless communication channel; (2) upload to the electronic medical record system the amount or concentration of at least one analyte present in the sample; or (3) determine a diagnosis of at least one condition in the subject and suggest a course of treatment.

[0085] The embodiments of the present disclosure may comprise or utilize special purpose or general purpose computing devices including computer hardware such as one or more processors and system memory, as discussed in more detail below. Embodiments within the scope of the present invention also include physical and other computer readable and recordable type media for carrying or storing computer executable instructions and / or data structures. Such computer readable recording media may be any available media that can be accessed by a general purpose or special purpose computer system. The computer readable media that store computer executable instructions according to the present invention are recordable type storage media or other physical computer storage media (devices) that are distinct from mere transitory carrier waves.

[0086] Computer-readable media that carry computer-executable instructions are transmission media. Thus, by way of example and not limitation, embodiments of the invention can include at least two different kinds of computer-readable, recordable media: computer storage media (devices) and transmission media.

[0087] Computer storage media (devices) include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code means in the form of computer-executable instructions or data structures and that can be accessed by a general-purpose or special-purpose computer and recorded on one or more recordable types of media (devices).

[0088] A "network" is defined as one or more data links or communication channels that enable the transfer of electronic data between computer systems and / or modules and / or other electronic devices. When information is transferred or provided over a network or another communications connection or channel (either hardwired, wireless, or a combination of hardwired or wireless) to a computer, the computer properly regards the connection as a transmission medium. A transmission medium may include a network and / or data links that may be used to carry desired program code means in the form of computer-executable instructions or data structures and that may be accessed by a general-purpose or special-purpose computer. Combinations of the above should also be included within the scope of computer-readable media.

[0089] Furthermore, upon reaching various computer system components, program code means in the form of computer executable instructions or data structures may be automatically transferred from transmission media to computer storage media (devices) (or vice versa). For example, computer executable instructions or data structures received over a network or data link may be buffered in RAM in a network interface module (e.g., "NIC") and then ultimately transferred to computer system RAM and / or less volatile computer storage media (devices) in the computer system. It should therefore be understood that computer storage media (devices) may be included in computer system components that also (or even primarily) utilize transmission media.

[0090] Computer-executable instructions include, for example, instructions and data that, when executed by a processor, cause a general purpose computer, special purpose computer, or special purpose processing device to perform a certain function or group of functions. Computer-executable instructions may be, for example, binaries, intermediate format instructions such as assembly language, or even source code. Although the subject matter has been described in language specific to structural features and / or methodological acts, it should be understood that the subject matter defined in the appended claims is not necessarily limited to the illustrated features or acts described herein. Rather, the described features and acts are disclosed as example forms of implementing the claims.

[0091] Those skilled in the art will appreciate that the present invention may be practiced in a networked computing environment having many types of computer system configurations including personal computers, desktop computers, laptop / notebook computers, message processors, handheld devices, multiprocessor systems, microprocessor-based or programmable consumer electronics, network PCs, minicomputers, mainframe computers, tablets, cell phones, PDAs, pagers, routers, switches, etc. The present invention may also be practiced in a distributed system environment where tasks are performed by both local and remote computer systems that are linked through a network (either by hardwired data links, wireless data links, or a combination of hardwired and wireless data links). In a distributed system environment, program modules may be located in both local and remote memory storage devices.

[0092] method The present disclosure also provides methods of using the subject devices, various steps and aspects of which will be described in more detail below.

[0093] In some cases, the subject method includes a method for reading a result indicating the presence or absence of an analyte in the sample. The method may include applying the sample to a first LFA cartridge, as described above. Samples of interest include physiological samples such as bodily fluids and biological samples, and the sample may be saliva, urine tears, semen, sputum, whole blood, plasma, and the like. In particular, the device may be used to test for various analytes, such as drugs of abuse, hormones, proteins, pathogens, plasma components, antibodies, and the like, using a suitable LFA cartridge designed for detection of a particular analyte. For example, the device is used with an LFA cartridge that includes a binding agent (e.g., a detection antibody) that specifically binds to the analyte.

[0094] In some embodiments, the device is used to detect pathogens or antibodies to pathogens. For example, the device can be used in combination with an LFA cartridge that contains binding agents designed to detect viral, bacterial, fungal, or parasitic pathogens, or antibodies thereto.

[0095] Exemplary viruses that may be assayed with the device include, without limitation, Adenoviridae, such as, but not limited to, adenovirus; Herpes simplex type 1, Herpes Herpesviridae, such as human herpesvirus type 8, Varicella-zoster virus, Epstein-Barr virus, human cytomegalovirus, and human herpesvirus type 8; Papillomaviridae, such as, but not limited to, human papillomavirus; Polyomaviridae, such as, but not limited to, BK virus, and JC virus; Poxviridae, such as, but not limited to, smallpox; Hepadnaviridae, such as, but not limited to, hepatitis B virus; Parvoviridae, such as, but not limited to, parvovirus B19; Astroviridae, such as, but not limited to, Caliciviridae, such as, but not limited to, Norwalk virus; Picornaviridae, such as, but not limited to, coxsackievirus, hepatitis A virus, poliovirus, and rhinovirus; Coronaviridae, such as, but not limited to, strains including severe acute respiratory syndrome-associated coronavirus, severe acute respiratory syndrome virus, and severe acute respiratory syndrome coronavirus 2; Hepatitis C virus, yellow fever virus, dengue virus, West Flaviviridae, such as Nile virus, TBE virus, and Zika virus; Matonaviridae, such as but not limited to rubella virus; Hepeviridae, such as but not limited to Hepatitis E virus; Retroviridae, such as but not limited to human immunodeficiency virus (HIV); Orthomyxoviridae, such as but not limited to influenza virus; Arenaviridae, such as but not limited to Lassa virus; Bunyaviridae, such as but not limited to Crimean-Congo hemorrhagic fever virus, Hantaan virus; Filoviridae, such as but not limited to Ebola virus and Marburg virus;Paramyxoviridae, including but not limited to measles virus, mumps virus, and parainfluenza virus; Pneumoviridae, including but not limited to respiratory syncytial virus; Rhabdoviridae, including but not limited to rabies virus; Hepatitis D virus; and Reoviridae, including but not limited to rotavirus, orbivirus, coltivirus, and bannavirus;

[0096] Exemplary pathogenic bacteria that may be assayed with the device include, without limitation, Gram-positive and Gram-negative bacteria, such as bacilli, bacteria, coccus, coccobacillus, and spirochetes, including, but not limited to, Bacillus, such as, but not limited to, Bacillus anthracis and Bacillus cereus; Bartonella, such as, but not limited to, Bartonella henselae and Bartonella quintana; Bordetella, such as, but not limited to, Bordetella pertussis; Borrelia, such as, but not limited to, Borrelia burgdorferi, Borrelia garinii, Borrelia afzelii, and Borrelia recurrentis; Brucella, such as, but not limited to, Brucella abortus, Brucella canis, Brucella melitensis, and Brucella suis; Chlamydia pneumoniae, Chlamydia trachomatis, and Chlamydophila Clostridium, such as but not limited to, Clostridium botulinum, Clostridium difficile, Clostridium perfringens, and Clostridium tetani; Corynebacterium, such as but not limited to, Corynebacterium diphtheriae; Enterococcus, such as but not limited to, Enterococcus faecalis and Enterococcus faecium; Escherichia, such as but not limited to, Escherichia coil; Francisella, such as but not limited to, Francisella tularensis; Haemophilus, such as but not limited to, Haemophilus influenzae;Helicobacter, such as but not limited to Helicobacter pylori; Legionella, such as but not limited to Legionella pneumophila, Leptospira, such as Leptospira interrogans, Leptospira santarosai, Leptospira weilii, and Leptospira noguchii; Listeria, such as but not limited to Listeria monocytogenes; Mycobacterium, such as but not limited to Mycobacterium leprae, Mycobacterium tuberculosis, and Mycobacterium ulcerans; Mycoplasma, such as but not limited to Mycoplasma pneumoniae; Neisseria, such as but not limited to Neisseria gonorrhoeae and Neisseria meningitidis; Pseudomonas, such as but not limited to Pseudomonas aeruginosa; Rickettsia, such as but not limited to Rickettsia rickettsii; Salmonella typhi and Salmonella Salmonella, such as Salmonella typhimurium; Shigella, such as but not limited to Shigella sonnei; Staphylococcus, such as but not limited to Staphylococcus aureus, Staphylococcus epidermidis, and Staphylococcus saprophyticus; Streptococcus, such as but not limited to Streptococcus agalactiae, Streptococcus pneumoniae, and Streptococcus pyogenes; Treponema, such as but not limited to Treponema pallidum; Ureaplasma, such as but not limited to Ureaplasma urealyticum; Vibrio, such as but not limited to Vibrio cholerae;Yersinia, including but not limited to Yersinia pestis, Yersinia enterocolitica, and Yersinia pseudotuberculosis;

[0097] Exemplary parasitic pathogens that may be assayed with the device include ectoparasites and endoparasites, including, without limitation, protozoa such as Excavata, including, but not limited to, Giardia intestinalis, Hexamita salmonis, Histomonas meleagridis, Trichonympha, Trichomonadida, Trypanosoma cruzi, Trypanosoma brucei rhodensiense, and Trypanosoma brucei gambiense; Amoebozoa, including Entamoeba histolytica, Naeglaria, and Acanthomoeba; Phytophthora infestans, Archaeplastida, Balantidium coli, Theileria parva, Theileria annulata, Phipicephalus appendiculatus, Spongospora subterranea, Mikrocytos mackini, and Prototheca. SAR including A. moriformis; and parasites including cestodes such as, but not limited to, Echinococcus, Hymenolepis, Taenia (e.g., T. multiceps, T. serialis, T. glomerata, and T. brauni); roundworms / nematodes such as, but not limited to, Necator americanus, Ancylostoma duodenale, Wuchereria bancrofti, Brugia malayi, Onchocerca volvulus, Ascaris lumbricoides, Trichuris, Trichostrongylus spp., Dracunculus medinensis, and Baylisascaris; and flukes / trematodes such as, but not limited to, amphistomes, Clonorchis sinensis, Fasciolopsis buski, Fascioloides magna, Fasciola hepatica, Opisthorchis, Paragonimus, and Schistosoma.

[0098] Exemplary pathogenic fungi that may be assayed with the device include, without limitation, Candida, such as but not limited to, Candida albicans; Aspergillus, such as but not limited to, Aspergillus fumigatus, Aspergillus flavus, and Aspergillus clavatus; Cryptococcus, such as but not limited to, Cryptococcus neoformans, Cryptococcus gattii, Cryptococcus laurentii, and Cryptococcus albidus; Histoplasma, such as but not limited to, Histoplasma capsulatum; Pneumocystis, such as but not limited to, Pneumocystis jirovecii; Stachybotrys, such as but not limited to, Stachybotrys chartarum; Blastomyces sp.; Coccidiodes, such as but not limited to, Coccidiodes immitis and Coccidiodes posadasii; Fusarium sp.; Paecilomyces sp.; Paracoccidioides brasiliensis; Penicillium marneffei; Pseudallescheria boydii; Scedosporium, including but not limited to Scedosporium apiospermum and Scedosporium prolificans; Rhizopus sp.; Mucor sp.; Absidia sp.; Cunninghamella sp.; Trichoderma longibrachiatium; and Trichosporon sp.

[0099] In particular, the device may be used in combination with an LFA cartridge designed to detect SARS-CoV-2 in a sample. In some embodiments, the LFA cartridge is designed to detect SARS-CoV-2 antigens or antibodies (e.g., IgG and / or IgM) against SARS-CoV-2 in a sample. For example, the LFA cartridge may include a test strip having a specific binding reagent (e.g., antibody) against an analyte suspected to be in the sample (e.g., SARS-CoV-2 or a portion or component thereof, anti-SARS-CoV-2 antibodies (e.g., IgG and / or IgM specific for SARS-CoV-2).

[0100] The method may further include disposing a positive control LFA cartridge, as described above, in a first LFA cartridge receiving portion of the device. The method may further include disposing a smart reader in a frame of the device. The smart reader may be any smart reader, such as a smartphone, digital camera, etc., as described above. The method may further include mating the base plate with the body, for example, by mating structures and protrusions provided by the body and the base plate, as described above. The method may further include capturing an image of the surface including the threshold intensity line, for example, by a smartphone camera. The method may further include analyzing the image to determine detection of the threshold intensity line.

[0101] In some cases, the digital reader may include or be in communication with a computer readable medium. In some cases, the digital reader includes or is in communication with a computer readable medium including instructions that cause the processor to detect the threshold intensity line and indicate successful detection of the threshold intensity line. In some cases, the digital reader includes or is in communication with a computer readable medium including instructions that cause the processor to detect an optically detectable assay result from the LFA cartridge and indicate successful detection of the optically detectable assay result. In some cases, the computer readable medium includes an algorithm that converts the visual readout from the interaction of the at least one analyte of interest with the at least one ligand into a numerical value related to the presence or amount of the at least one analyte of interest present in the sample.

[0102] In certain embodiments, a digital reader, e.g., a detector such as a smartphone camera, will be used to capture an image of the surface including the assay area (and / or control area) and / or threshold intensity line of the LFA cartridge. The CCD of the camera may capture the image. In this image, both the threshold intensity line and the assay area (e.g., optically detectable assay result) may be present. The image of the threshold intensity line may be captured and analyzed before or after the image of the assay area is captured or analyzed. In some cases, the image of the threshold intensity line is captured and analyzed simultaneously with the image of the assay area. The digital image may then undergo digital signal processing using a selected digital processing algorithm to simultaneously generate representative images of the threshold intensity line and color bands for the assay area. The digital processing algorithm may then take an integral based on a predefined area within each of the bands and add the intensity values ​​of each of these pixels to generate a final intensity count. The intensity value of the count may be in the range of at least 0-128 for a 7-bit intensity depth grayscale image, 0-255 for an 8-bit intensity depth grayscale image, or any other range of the intensity depth grayscale image depending on the camera imaging algorithm. The intensity values ​​may also be in the range of 0-16384 for 2-color images with 7-bit color intensity depth, 0-65536 for 2-color images with 8-bit color intensity depth, and 0-16777216 for 3-color images with 8-bit color intensity depth. The intensity values ​​may also be in ranges resulting from processing these values ​​with either the camera imaging algorithm or a post-processing algorithm on the reader processor. The intensity counts may be compared to a predefined standard curve (or set of standard parameters) obtained from LFA imaging from various positive and negative samples to allow either a qualitative or quantitative evaluation of the test results.

[0103] A single LFA cartridge can accommodate multiple types of different antibodies, each conjugated with a different dye, and multiple capture bands, each immobilized with a different antibody. A single light source can illuminate all the dyes simultaneously, and a detector device can capture the emitted signal from the multiple bands simultaneously.

[0104] Capturing an image of the surface including the optically detectable markings includes illuminating the surface. Emission from various reporters (e.g., dyes) present in the markings of the LFA cartridge can be excited by several light sources, such as, for example, an LED light source. Illumination by the light source can generate an optically detectable signal including at least one of emission from the reporter (e.g., fluorescence), color, reflectance, diffuse scattering (i.e., scattering and absorbance), elastic light scattering, chemiluminescence, chemifluorescence, transmission, or absorbance. A lens (e.g., a collimating lens) and a detector (e.g., a CCD or CMOS camera) can be used to collect data from the reporter. A collimating lens and a CCD camera are used to collect the emitted light. The intensity of each of the markings and the concentration of each of the analytes can be quantified as described above.

[0105] The light source may include at least one of a camera flash, an on-camera autofocus illuminator, ambient light, sunlight, an LED light, an incandescent lamp, or a gas discharge lamp. For example, the light source may be from a micro-LED lamp contained in the housing. The micro-LED may be selected to emit a specific wavelength adapted to one or more assay conditions. The micro-LED may be powered by drawing power from the battery of the digital camera device.

[0106] A wavelength filter may be interposed between the light source and the lateral flow chromatography immunoassay cartridge. For example, if the assay is a fluorescent assay, a wavelength filter may be used to provide a particular wavelength of light from the light source to excite fluorescent emission from the assay system. Similarly, a particular colored dye may provide a better signal when excited by a selected wavelength of light.

[0107] The light source may include at least one focusing device (e.g., a collimating lens) for focusing the light source onto the lateral flow chromatography immunoassay cassette. For example, the focusing device may be used to increase the amount of incident light on the analysis zone of the lateral flow chromatography immunoassay cassette. In another example, the focusing device may be used to focus ambient light or sunlight onto the analysis zone of the lateral flow chromatography immunoassay cassette to enable a digital camera device to capture at least one image of the assay output.

[0108] The digital reader may include, or be in communication with, a computer-readable medium containing instructions that cause a processor to: analyze an image containing an optically detectable assay result captured by the digital reader; and indicate the presence or absence of an analyte in a sample assayed by the LFA cartridge.

[0109] The computer readable medium may include instructions to cause the processor to compare the signal detected from the optically detectable assay result with the signal from the threshold intensity line to determine the validity of the optically detectable assay result. In some cases, the computer readable medium may include instructions to cause the processor to execute an algorithm that provides an indication of an error when the threshold intensity line is not detected. When the threshold intensity line is not detected, the computer readable medium may include instructions to cause the processor to determine that the image analysis of the optically detectable assay result is invalid and to discard the result. When the threshold intensity line is not detected, the computer readable medium may include instructions to cause the processor to adjust the focus of the detector, e.g., a smartphone camera, and adjust the brightness of the light source, e.g., a smartphone light. In some cases, when the threshold intensity line is not detected, the computer readable medium may include instructions to cause the processor to provide an indication to take corrective action to facilitate detection of the threshold intensity line, such as, for example, an indication to repeat the capture of the image, clean the reader camera, adjust the reader light, and / or adjust the focus of the detector.

[0110] The instructions may cause the processor to do any of the following: (1) receive a user-initiated request to convert a visual signal readout of the LFA cartridge into a numerical value; (2) in response to the request, identify at least one visual signal readout of the LFA cartridge; (3) capture at least one digital photographic image of the at least one visual signal readout of the LFA cartridge; (4) convert the at least one digital photographic image into at least one numerical value proportional to at least one of the intensity, density, or pixel count of the at least one digital photographic image of the at least one visual signal readout of the immunoassay device; and (5) use the at least one numerical value to determine the amount or concentration of at least one analyte present in the sample. This numerical value may then be displayed on a screen located on the detector device and / or stored, interpreted, or transmitted to a database. In some cases, the instructions cause the processor to implement a method for interpreting a numerical value related to the presence or amount of at least one analyte present in the sample.

[0111] When a threshold intensity line is detected, the method may further include: placing a first LFA cartridge in a first LFA cartridge receiving portion of the device; capturing an image of the surface containing the optically detectable assay result; and analyzing the image to indicate the presence or absence of the analyte in the sample assayed by the LFA cartridge.

[0112] When the threshold intensity line is not detected, the method may further include: determining that the image analysis of the first LFA cartridge is invalid, discarding the results from the image analysis of the first LFA cartridge, and / or providing an indication of an error that the threshold intensity line is not detected and / or the assay result is invalid. In some cases, the method may further include adjusting the focus of the detector, e.g., smartphone camera, and adjusting the brightness of the light source, e.g., smartphone light. In some cases, the method may further include providing an indication to take corrective action to facilitate detection of the threshold intensity line, such as, for example, an indication to repeat image capture, clean the reader camera, adjust the reader light, and / or adjust the focus of the detector. In some cases, the method may further include: capturing an image of a surface including the threshold intensity line; and analyzing the image to determine detection of the threshold intensity line.

[0113] When the threshold intensity line is detected, the method may further include: capturing an image of a surface of the first LFA cartridge containing the optically detectable assay result, and analyzing the image to indicate the presence or absence of the analyte in the sample assayed by the LFA cartridge. In some cases, the method may further include providing a "validity score" for the image analysis of the optically detectable assay result under given circumstances (e.g., ambient light intensity, degree of dust / dirt contamination on the optical surface, camera autofocus accuracy, etc.).

[0114] A method for reading a result indicating the presence or absence of an analyte in a sample may include: applying the sample to an LFA cartridge including an assay area and a positive control area as described above, placing the LFA cartridge in a first LFA cartridge receiving portion or a second LFA cartridge receiving portion of the device as described above, placing a digital reader in a frame of the device as described above, mating the body to a base plate of the device, capturing an image of the surface of the LFA cartridge including the assay area and the positive control area; capturing an image of the threshold intensity line; and analyzing the image to determine detection of the threshold intensity line.

[0115] When a threshold intensity line is detected, the method may further include: analyzing the image to indicate the presence or absence of an analyte in the sample assayed by the LFA cartridge.

[0116] When the threshold intensity line is not detected, the method may further include: determining that the image analysis of the first LFA cartridge is invalid, discarding the results from the image analysis of the first LFA cartridge, and / or providing an indication of an error that the threshold intensity line is not detected and / or the assay result is invalid. In some cases, the method may further include adjusting the focus of the detector, e.g., smartphone camera, and adjusting the brightness of the light source, e.g., smartphone light. In some cases, the method may further include providing an indication to take corrective action to facilitate detection of the threshold intensity line, such as, for example, an indication to repeat image capture, clean the reader camera, adjust the reader light, and / or adjust the focus of the detector. In some cases, the method may further include: capturing an image of a surface including the threshold intensity line; and analyzing the image to determine detection of the threshold intensity line.

[0117] When a threshold intensity line is detected, the method may further include analyzing the image to indicate the presence or absence of an analyte in the sample assayed by the LFA cartridge.

[0118] example As can be understood from the disclosure provided above, the present disclosure has a wide variety of applications. Thus, the following examples are presented to provide those of skill in the art with a complete disclosure and description of how to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention, nor are they intended to represent that the following experiments are all or the only experiments performed. Those of skill in the art will readily recognize a variety of non-critical parameters that can be changed or modified to achieve essentially similar results. Thus, the following examples are presented to provide those of skill in the art with a complete disclosure and description of how to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention, nor are they intended to represent that the following experiments are all or the only experiments performed. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, dimensions, etc.) used, but some experimental error and deviation should be accounted for.

[0119] Specific Embodiments FIG. 1 provides a schematic diagram of a device of the present disclosure. The device includes a body 101 for receiving a smartphone 100. Most of the surface of the smartphone 100 is covered by the body 101 of the device, except for a touch screen that is framed by the body. The body further provides an opening for attaching a power cord to the smartphone 100 when the smartphone is held in the body. The body further provides an opening 107 for accessing an on / off switch of the smartphone at a side of the frame. FIG. 1 further illustrates a base plate 104 having a first receiving portion 103 present at one end of the base plate and a second receiving portion 105 present at an opposite end of the base plate. A first LFA cartridge 102 can be inserted into the first receiving portion 103 in a first orientation relative to a planar surface of the smartphone, and a second FFA cartridge 106 can be inserted into the second receiving portion in a second orientation relative to the same planar surface of the smartphone.

[0120] FIG. 2A shows a top view of one embodiment of a lateral flow assay cartridge having a base 201 with an assay region and a control region. The assay region and the control region are in the same plane. The assay region includes a sample deposition area 204 coupled to a test region 200 with a test strip and reagents for performing a rapid diagnostic test assay. The test region includes a control line (C) to indicate that the test was performed properly. In regions (1) and (2), lines of variable intensity may be shown depending on the target found in the sample. For example, line (1) may show an intensity depending on the concentration of Flu A antibodies in the sample, while line (2) shows an intensity depending on the concentration of Flu B antibodies in the sample. A threshold intensity line 203 is shown disposed on a durable material plate 202. The control line (C) intensity may be quite low in the case of early stages of infection, so the assay results must be interpreted appropriately. By reading a relatively low intensity line, such as a threshold intensity line present simultaneously on the durable material plate (or immediately prior to sample reading, or at least once a day, or within another time interval), and comparing it to an acceptance limit, it can be ensured that the optical path and interpretation software algorithms are operating properly to avoid interpretation errors.

[0121] 2B shows a side view of one embodiment of a lateral flow assay cartridge 208 positioned under a camera device 206 (e.g., a smartphone). The LFA cartridge is positioned such that the test area 210 of the LFA cartridge and a threshold intensity line disposed on a durable plate material 209 fall within the image field 207 of the camera lens 205 of the camera device 206.

[0122] 3 illustrates a perspective view of one embodiment of the device. A body for receiving a smartphone is attached to a base plate for receiving one or more LFA cartridges. The body includes a frame that extends around the sides of the smartphone, but leaves the touch screen and charging port exposed.

[0123] 4 illustrates a first end view of one embodiment of the subject device. A body for receiving a smartphone is attached to a base plate for receiving one or more LFA cartridges. The body includes a frame that extends around the sides of the smartphone, but leaves the touch screen and charging port exposed.

[0124] 5 illustrates an overhead view of one embodiment of the subject device. The body includes a frame that extends around the sides of the smartphone, but leaves the touch screen and charging port exposed.

[0125] 6 illustrates a side view of one embodiment of the subject device. A body for receiving a smartphone is attached to a base plate for receiving one or more LFA cartridges.

[0126] FIG. 7 illustrates a bottom view of one embodiment of a base plate of the subject device.

[0127] 8 illustrates a second end view of one embodiment of the subject device. A body for receiving a smartphone is attached to a base plate for receiving one or more LFA cartridges.

[0128] 9A illustrates a view of one embodiment of a device of the present disclosure from the end facing the top lateral edge of a smartphone having a camera. A power cord 901 is coupled to the smartphone at the opposite end of the body. A base plate 903 for receiving an LFA cartridge 902 may be coupled to the body 900. A top lateral edge 922 of the LFA cartridge 902 is angled at a horizontal angle of 3 degrees away from a planar surface 923 of the frame of the body 900 that houses the smartphone.

[0129] 9B illustrates a side view of one embodiment of a device of the present disclosure. The device includes a body 912 that can be coupled to a base plate 907 for receiving an LFA cartridge 906. The body 912 houses a smartphone that is coupled to a power cord 904. An upper vertical edge 924 of the LFA cartridge 906 slopes at a 5 degree vertical angle toward a planar surface 905 of the frame of the body 912 that houses the smartphone.

[0130] 9C illustrates a view of one embodiment of a device of the present disclosure from the end facing the bottom lateral edge of a smartphone having a charging port. The device includes a body 908 for housing the smartphone. The body includes a frame 925 that covers the face of the smartphone but leaves the touch screen 921 exposed. A power cord 909 is coupled to the smartphone. The device further includes a base plate 910 that can be coupled to the body 908. The base plate 911 can receive an LFA cartridge.

[0131] FIG. 10A illustrates an overhead view of one embodiment of a base plate 1000 for receiving an LFA cartridge. The base plate has a first receiving portion 1001 and a second receiving portion 1004, each for receiving at least one LFA cartridge. The first receiving portion 1001 is shown to hold one LFA cartridge 1002. The first receiving portion has a set of longitudinal edges 1 and 1' and a set of transverse edges 2 and 2'. FIG. 10B illustrates a perspective view of one embodiment of the first receiving portion 1001. The longitudinal edges and transverse edges form a support surface 3 therebetween.

[0132] FIG. 11 illustrates a vertical angle 1101 formed between a planar surface 1100 of a frame of a body for receiving a smartphone and a support surface 3 of a receiving part 1102. A side view facing a longitudinal edge 1' of the receiving part 1102 is shown. The planar surface 1100 extends in the longitudinal direction and intersects with the plane of the support surface at an angle 1101. The plane of the support surface between the longitudinal edges 1' and 1 is inclined towards the planar surface 1100 at the vertical angle 1101 such that the transverse edge 2 is positioned closer to the planar surface 1100 than the transverse edge 2'.

[0133] Fig. 12 illustrates an example of a horizontal angle 1104 formed between a planar surface 1103 of a frame of a body for receiving a smartphone and a receiving portion 1105 of a base plate. A front view facing a lateral edge 2 of the receiving portion is shown. The planar surface 1103 extends laterally and intersects with the plane of the support surface at an angle 1104. The plane o of the support surface between the lateral edges 2 and 2' is inclined away from the planar surface 1103 such that the longitudinal edge 1' is positioned further away from the planar surface 1103 than the longitudinal edge 1.

[0134] Although the above invention has been described in some detail by way of illustration and example for clarity of understanding, it will be readily apparent to those skilled in the art that certain changes and modifications may be made in light of the teachings of the present invention without departing from the spirit or scope of the appended claims. It should also be understood that the terminology used herein is for the purpose of describing only particular embodiments, and is not intended to be limiting, since the scope of the present invention is limited only by the appended claims. Thus, the above merely illustrates the principles of the present invention. Those skilled in the art will appreciate that various configurations, not expressly described or shown herein, may be devised which embody the principles of the present invention and are within the spirit and scope thereof. Furthermore, all examples and conditional language recited herein are intended primarily to aid the reader in understanding the principles of the present invention and the concepts contributed by the inventor to further the art, and should not be construed as being limited to such specifically recited examples and conditions. Furthermore, all statements herein reciting principles, aspects, and embodiments of the present invention, as well as specific examples thereof, are intended to embrace both structural and functional equivalents thereof. Additionally, such equivalents are intended to include both currently known equivalents and equivalents developed in the future, i.e., any elements developed that perform the same function, regardless of structure. Thus, the scope of the present invention is not intended to be limited to the exemplary embodiments shown and described herein. Rather, the scope and spirit of the present invention is embodied by the appended claims.

Claims

1. A device for receiving a digital reader and a lateral flow assay (LFA) cartridge, the device comprising a body and a base plate; The main body, a wall enclosing a space, the wall including a top portion and a bottom portion; a frame coupled to an upper portion of the wall, the frame configured to receive a digital reader; a mating structure defined by a bottom portion of the wall, the mating structure configured to removably couple to the base plate; The base plate includes a first surface and a second surface defining a space therebetween, the space comprising: a first LFA cartridge receiving portion; the first LFA cartridge receiving portion includes a substantially planar first support surface that receives and holds the LFA cartridge in a substantially fixed position; The device, wherein the first support surface is at a first fixed orientation relative to a planar space defined by the frame.

2. 2. The device of claim 1, wherein the space further comprises a second LFA cartridge receiving portion having a substantially planar second support surface for receiving and holding the LFA cartridge, the second support surface being in a second fixed orientation relative to the planar space defined by the frame.

3. The device of claim 2 , wherein the first and second fixed orientations are different.

4. The device of claim 2 , wherein the first and second fixed orientations are the same.

5. 2. The device of claim 1, wherein the first fixed orientation comprises a horizontal angle, measured as the tilt of the first lateral edge away from the planar surface, in the range of +1 degree to +10 degrees, or -1 degree to -10 degrees.

6. 2. The device of claim 1, wherein the first fixed orientation comprises a vertical angle, measured as the inclination of the first vertical edge toward the planar surface, in the range of -15 degrees to -1 degree, or +1 degree to +15 degrees.

7. 3. The device of claim 2, wherein the second fixed orientation comprises a horizontal angle, measured as the slope of the second lateral edge away from the planar surface, ranging from +1 degree to +10 degrees, or from -10 degrees to -1 degree.

8. 3. The device of claim 2, wherein the second fixed angle is a vertical angle measured as the inclination of the second vertical edge toward the planar surface, in the range of −15 degrees to −1 degree, or +1 degree to +15 degrees.

9. The device of claim 1 , wherein the first surface comprises a protrusion that fits into the mating structure.

10. 10. The device of claim 1, wherein the device is manufactured from an opaque material.

11. 10. The device of claim 1 , wherein the device is fabricated from a light absorbing material.

12. 10. The device of claim 1 , wherein a first surface of the base plate faces the interior of the device and comprises a light absorbing material, or a second surface of the base plate faces the interior of the device and comprises a light absorbing material.

13. The device of claim 2, wherein the base plate has a first LFA cartridge receiving portion and a second LFA cartridge receiving portion, and the mating structure and at least a portion of the base plate have axisymmetric shapes such that the mating structure and the base plate can be coupled in two orientations by rotating either the mating structure or the base plate.

14. The device of claim 13 , wherein the mating structure and at least a portion of the base plate have a rectangular shape.

15. The device of claim 13 , wherein the mating structure and at least a portion of the base plate have a square shape.

16. 16. The device of claim 1, further comprising a threshold intensity line present on the first surface of the base plate and adjacent the first LFA cartridge receiving portion or the second LFA cartridge receiving portion.

17. The device of claim 16 , wherein the threshold intensity line is disposed directly on the first surface.

18. 17. The device of claim 16, wherein the threshold intensity line is disposed on a substantially planar solid support attached to the first surface.

19. 20. The device of claim 18, wherein the threshold intensity line has a reflection intensity that is at least 0.1-10% lower than the surface reflection intensity of the solid support.

20. 20. The device of claim 18 or 19, wherein the solid support comprises a ceramic sheet.

21. 1. A system for reading a lateral flow assay (LFA) cartridge, the system comprising: A device according to any one of claims 1 to 20; Digital reader and A system comprising: an LFA cartridge including an assay area containing an optically detectable assay result, the optically detectable assay result being generateable by contacting the LFA cartridge with a sample containing or suspected of containing an analyte; and

22. 22. The system of claim 21, wherein the LFA cartridge comprises a positive control area comprising an optically detectable marking.

23. 23. The system of claim 21 or 22, comprising at least two LFA cartridges.

24. 24. The system of any one of claims 21 to 23, wherein the digital reader includes a computing device equipped with a camera, a light source, and a touch screen.

25. 25. The system of claim 24, wherein the digital reader is a digital camera.

26. 25. The system of claim 24, wherein the digital reader is a smartphone.

27. The digital reader includes or is in communication with a computer-readable medium that includes instructions, the instructions being transmitted to a processor resident within the digital reader or connected to the digital reader to: analyzing the image containing the optically detectable assay results captured by the digital reader; 27. The system of any one of claims 21 to 26, which indicates the presence or absence of an analyte in a sample assayed by the LFA cartridge.

28. 28. The system of any one of claims 21 to 27, wherein the digital reader comprises or is in communication with a computer readable medium containing instructions, the instructions causing the processor to detect the threshold intensity line.

29. 30. The system of claim 28, wherein the computer readable medium includes instructions that cause the processor to execute an algorithm that provides an indication of an error when a threshold intensity line is not detected.

30. 30. The system of claim 28, wherein the computer-readable medium comprises instructions that cause the processor to compare a signal detected from an optically detectable assay result with a signal from a threshold intensity line to determine the validity of the optically detectable assay result.

31. 31. The system of any one of claims 21 to 30, wherein the assay area of ​​the LFA cartridge comprises a binding agent that specifically binds to the analyte.

32. The system of claim 31 , wherein the binding agent is an antibody.

33. 33. The system of any one of claims 21 to 32, wherein the analyte is a pathogen or an antibody to a pathogen.

34. 34. The system of claim 33, wherein the pathogen is a viral pathogen, a bacterial pathogen, a fungal pathogen, or a parasitic pathogen.

35. 35. The system of claim 34, wherein the viral pathogen is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

36. The assay area of ​​the LFA cartridge is A recombinant SARS-CoV-2 antigen; An anti-human IgG antibody; and an anti-human IgM antibody.

37. The system of claim 36 , wherein the anti-human IgG antibody is a monoclonal antibody.

38. The system of claim 36 or 37, wherein the anti-human IgM antibody is a monoclonal antibody.

39. The system of any one of claims 36 to 38, wherein the recombinant SARS-CoV-2 antigen comprises a label.

40. 40. The system of claim 39, wherein the recombinant SARS-CoV-2 antigen comprises a colloidal gold label or a latex bead label.

41. The assay area of ​​the LFA cartridge is a first anti-SARS-CoV-2 antibody; and and a second anti-SARS-CoV-2 antibody.

42. 42. The system of claim 41, wherein the first anti-SARS-CoV-2 antibody is immobilized.

43. 42. The system of claim 41 , wherein the second anti-SARS-CoV-2 antibody comprises a label.

44. 42. The system of claim 41, wherein the first anti-SARS-CoV-2 antibody and the second anti-SARS-CoV-2 antibody recognize different epitopes of SARS-CoV-2.

45. 42. The system of claim 41, wherein a sample pad comprises the second anti-SARS-CoV-2 antibody.

46. 42. The system of claim 41, wherein a test line comprises the first anti-SARS-CoV-2 antibody.

47. 47. A method of detecting an analyte using the system of any one of claims 21 to 46, the method comprising contacting the LFA cartridge with a sample containing or suspected of containing the analyte, and the assay area producing an optically detectable assay result indicative of the presence or absence of the analyte.

48. 48. The method of claim 47, wherein the analyte is a pathogen or an antibody to a pathogen.

49. 49. The method of claim 48, wherein the pathogen is a viral pathogen, a bacterial pathogen, a fungal pathogen, or a parasitic pathogen.

50. 50. The method of claim 49, wherein the viral pathogen is severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

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