Devices, systems and methods for antimicrobial drug susceptibility testing

Abstract

Various devices, systems, and methods for determining the susceptibility of an infectious pathogen to one or more anti-infective agents are disclosed. In one aspect, a multiplexing system may include a microwell plate, a sensor array cover configured to cover the microwell plate, and a reader for receiving the microwell plate covered by the sensor array cover. The microwell plate may include wells including a test well comprising an anti-infective drug and at least one control well free of any anti-infective drug. Each aperture may be configured to receive and accommodate an aliquot of a sample. The sensor array cover may include a plurality of sensor cells. Each sensor cell may be configured to extend to a well of the microwell plate. Each sensor unit may include an active electrode and a reference electrode read by the reader to determine the susceptibility of an infectious pathogen to an infectious drug.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 507,956, filed on June 13, 2023, and U.S. Provisional Application No. 63 / 373,777, filed on August 29, 2022, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present invention relates generally to diagnostic devices, systems and methods, and more particularly to devices, systems and methods for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs. Background Art

[0004] More and more disease-causing bacteria are acquiring antibiotic resistance, and new forms of resistance continue to emerge across borders at an alarming rate. The Centers for Disease Control (CDC) has called antibiotic resistance one of the greatest public health challenges of our time. In the United States alone, more than 2 million people are infected with antibiotic-resistant infections each year, and the death rate continues to rise. Providing a rapid and low-cost antibiotic susceptibility test (AST) that can test multiple samples simultaneously will become increasingly important to control this rapidly evolving problem.

[0005] The current gold standard AST laboratory process typically requires tedious overnight cultures, takes several days, and needs to be performed by highly trained personnel. The following steps are usually taken: i) blood culture, ii) pathogen isolation on agar medium, iii) preparation of a standard inoculum of 0.5 McFarland (MF) from bacterial colonies, and iv) AST for identification of antibiotic treatment. Speeding up this process can have a huge impact on patient survival, reduce costs, and reduce the likelihood that doctors will use broad-spectrum antibiotics that may cause antibiotic resistance.

[0006] Although new technologies are being developed, most still require visual interpretation of results, which can affect the accuracy of such results. In addition, some rapid AST systems that use light-based detection methods cannot process samples containing blood, which absorbs light and skews the results.

[0007] Therefore, there is a need for a solution that can detect bacterial growth, even in the presence of blood, without the need for labor-intensive steps. Such a solution should be cost-effective to manufacture and provide accurate results. Such a solution should also allow for multiplexing including simultaneous reading of multiple wells to rapidly determine the minimum inhibitory concentration (MIC). Summary of the invention

[0008] Disclosed herein are diagnostic test devices, systems, and methods for determining the susceptibility of infectious pathogens to one or more anti-infective drugs. In one embodiment, a system for determining the susceptibility of infectious pathogens to one or more anti-infective drugs is disclosed. The system may include a microplate comprising a plurality of holes. The plurality of holes may include a test hole and at least one control hole. Each hole may be configured to contain an aliquot containing an infectious pathogen sample. At least one test hole may contain an anti-infective drug, and the control hole may not contain an anti-infective drug.

[0009] In some embodiments, the sensor array cover can include a cover top and a flexible substrate connected to the bottom surface of the cover top.The sensor array cover can be configured to cover a microwell plate.

[0010] The flexible substrate may include a plurality of substrate strips or substrate segments partially cut out from the remaining portion of the flexible substrate.At least one substrate strip or substrate segment of the flexible substrate may be curled or bent vertically downward relative to the surrounding portion of the flexible substrate.

[0011] The active electrode can be arranged on each substrate strip or substrate segment that is curled or bent vertically downward, and the reference electrode can be arranged on each substrate strip or substrate segment that is curled or bent vertically downward. Each substrate strip or substrate segment including the active electrode and the reference electrode can be regarded as a sensor unit.

[0012] The sensor array cover may include a plurality of sensor units extending from a bottom surface of the sensor array cover. Each sensor unit may be configured to extend into a well of a microplate such that the sensor unit is at least partially immersed in an aliquot of the sample within the well.

[0013] The system may also include a reader, which may be configured to receive the microwell plate and the sensor array cover covering the microwell plate in a receiving well of the reader. The reader may include conductive contacts for contacting the active electrode and the reference electrode of the sensor unit.

[0014] The reader can be configured to determine the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in solution characteristics of sample aliquots in test wells containing the anti-infective drug and any changes in solution characteristics of sample aliquots in control wells over a period of time.

[0015] A method for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs is also disclosed. The method may include introducing an aliquot of a sample containing an infectious pathogen into a well of a microplate. The well may include a test well and at least one control well. At least one test well may contain an anti-infective drug, and the control well may not contain an anti-infective drug.

[0016] The method may further include covering the microplate with a sensor array cover. The sensor array cover may include a plurality of sensor cells extending from a bottom surface of the sensor array cover. Each sensor cell may be configured to extend into a well of the microplate such that the sensor cell is at least partially immersed in an aliquot of the sample in the well. Each sensor cell may include an active electrode and a reference electrode.

[0017] The method may also include inserting the microplate covered by the sensor array cover into a reader. The reader may include conductive contacts for contacting the active electrodes and reference electrodes of the sensor units. The method may also include determining the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in the solution characteristics of the sample aliquots in the test wells containing the anti-infective drug and any changes in the solution characteristics of the sample aliquots in the control wells over a period of time.

[0018] The method may further include diluting the sample with a diluent to a dilution ratio of about 1:1 to about 1:10000 before introducing the sample into the well of the microplate. The method may further include incubating the microplate covered by the sensor array cover in a reader at an incubation temperature of about 30°C to about 40°C.

[0019] In some embodiments, the microwell plate can include 24 to 96 wells. The sensor array cover can include 24 to 96 sensor units.

[0020] In some embodiments, the anti-infective drug in the test wells can be lyophilized or dried.

[0021] In some embodiments, the anti-infective drug within the test well may be in aqueous form.

[0022] In some embodiments, any changes in the properties of the solution in the well can be detected without adding any exogenous reporter molecules to the well.

[0023] In some embodiments, the sample may include a body fluid or a bacterial culture derived from a body fluid. For example, the sample may be a positive blood culture.

[0024] In some embodiments, the infectious pathogen may include bacteria.

[0025] In some embodiments, the anti-infective drug may include a bacteriostatic anti-infective drug, a bactericidal anti-infective drug, or a combination thereof.

[0026] In some embodiments, the infectious pathogen may include a fungus.

[0027] In some embodiments, anti-infective drugs may include antifungal agents.

[0028] In some embodiments, the active electrode can include a redox active material.

[0029] In some embodiments, the redox active material may be a noble metal. For example, the noble metal may be platinum or gold. In other embodiments, the redox active material may be a conductive metal oxide, such as iridium oxide, ruthenium oxide, or any combination or alloy of these materials with a noble metal. In other embodiments, the redox active material may be a carbon-based electrode.

[0030] In some embodiments, the reference electrode can include a reference electrode substance.

[0031] In some embodiments, the reference electrode material may include at least one of silver / silver chloride (Ag / AgCl) and carbon.

[0032] In some embodiments, the reference electrode material may be coated or covered by an ion exchange membrane.

[0033] In some embodiments, the ion exchange membrane may be a sulfonated tetrafluoroethylene based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane.

[0034] In some embodiments, the cover top may include a post extending from the bottom surface of the cover top. The post may be configured to push against or press against the substrate strip or substrate segment so that the substrate strip or substrate segment maintains its curled or bent configuration.

[0035] In some embodiments, at least one substrate strip or substrate segment can be abutted or pressed against by at least one post such that a portion of the substrate strip or substrate segment is substantially perpendicular to the portion of the flexible substrate connected to the cover top.

[0036] In some embodiments, the flexible substrate can be made in part of a flexible polymer material.

[0037] In some embodiments, the flexible polymer material may be made in part from polyethylene terephthalate (PET).

[0038] In some embodiments, the flexible polymer material may be a flexible printed circuit board (PCB) material.

[0039] In some embodiments, the flexible PCB material may be polyimide.

[0040] In some embodiments, the flexible substrate can be made in part from a conductive metal substrate. For example, the conductive metal substrate can be a stainless steel foil.

[0041] In some embodiments, the cap top may be made in part from at least one of polystyrene, polypropylene, and cyclic olefin copolymer.

[0042] In some embodiments, at least one of the active electrode and the reference electrode can be a screen printed electrode (SPE), such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is screen printed onto a flexible substrate.

[0043] In some embodiments, at least one of the active electrode and the reference electrode can be a plated electrode such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is plated onto the flexible substrate.

[0044] In some embodiments, at least one of the active electrode and the reference electrode can be a sputter deposited electrode, such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is sputter deposited onto the flexible substrate.

[0045] In some embodiments, the sensor array cover can be disposable or single-use.

[0046] In some embodiments, the flexible substrate may include an electrical contact pad disposed on the flexible substrate. The top of the cover may expose the electrical contact pad. The active electrode may be electrically connected to the electrical contact pad via conductive traces. The reference electrode may be electrically connected to the electrical contact pad via additional conductive traces.

[0047] In some embodiments, the reference electrode can be a pseudo-reference electrode.

[0048] In some embodiments, the flexible substrate can be coupled to the bottom surface of the cover top by at least one of a biocompatible adhesive and a fastener. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1A A perspective view of one embodiment of a testing device including a sensor array cover and a microwell plate is shown.

[0050] Figure 1B A perspective view showing the underside of the sensor array cover.

[0051] Figure 1C A perspective view of one embodiment of a testing device is shown in an assembled configuration.

[0052] Figure 1D A top view of the test device is shown in an assembled configuration.

[0053] Figure 1E A bottom view of the test device is shown in an assembled configuration.

[0054] Figure 1F A perspective view of one embodiment of a testing device is shown in an assembled configuration, with the side of the device shown in cross-section for illustration purposes.

[0055] Figure 1G is a close up view of the posts abutting the base strip to allow the base strip to maintain a curled or bent configuration.

[0056] Figure 1H A schematic diagram of a sensor cell is shown, comprising an active electrode of the sensor cell and a reference electrode immersed in an aliquot of a sample in a microplate well.

[0057] Figure 2A is a black and white image showing one embodiment of a sensor array cover.

[0058] Figure 2B Black and white image showing a close-up of a sensor unit implemented as a substrate strip immersed in an aliquot of a sample in a microplate well.

[0059] Figure 3A A method for creating screen-printed electrodes on a flexible substrate is shown.

[0060] Figure 3B A schematic diagram showing that a reference electrode material portion is disposed on a flexible substrate and the reference electrode material is entirely covered by an ion exchange membrane.

[0061] Figure 4A An ORP bacterial growth curve obtained using an embodiment of a diagnostic device having screen-printed electrodes is shown. An ORP bacterial growth curve obtained using a commercially available ORP sensor is also shown.

[0062] Figure 4B Various ORP bacterial growth curves are shown, which illustrate the growth behavior of susceptible and resistant bacteria in test wells and control wells.

[0063] Figure 5 An ORP bacterial growth curve obtained using an embodiment of a test device having a sputter deposited electrode is shown. An ORP bacterial growth curve obtained using a commercially available ORP sensor is also shown.

[0064] Figure 6 Shown is an ORP bacterial growth curve obtained using an embodiment of a test device having a plating electrode.

[0065] Fig. 7A and Figure 7BA perspective view and a front view, respectively, are shown of a reader for receiving a test device and detecting a change in a characteristic of a sample solution within a well of the test device.

[0066] Figure 7C A high level circuit diagram is shown showing how the reader reads the electrodes (active and reference electrodes) of the sensor cell.

[0067] Fig.7D Schematic diagram showing some of the electronics in the reader involved in processing the signals obtained from the sensor unit.

[0068] Figure 8 The various steps for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs are shown.

[0069] Fig.9A is a table showing the performance results of Gram-negative artificial positive blood cultures (PBC) in the presence of several antibiotics.

[0070] Fig. 9B is a table showing expected performance results for Gram-negative PBC in the presence of several antibiotics.

[0071] Fig. 9C It is shown Fig.9A Time-result graph for Gram-negative artificial PBC shown in .

[0072] Fig. 10A A side cross-sectional view of another embodiment of a test device is shown that includes a sensor array cover including sensor cells having active electrodes implemented as pins extending into wells of a microplate.

[0073] Fig. 10B is a black and white image showing a platinum coated post used as an active electrode. DETAILED DESCRIPTION

[0074] Variations of the devices, systems, and methods described herein may best be understood from the detailed description when read in conjunction with the accompanying drawings. It is emphasized that, in accordance with common practice, various features in the drawings may not be drawn to scale. The dimensions of certain features have been exaggerated or reduced for clarity, and not all features may be visible or labeled in every drawing. The drawings are for illustrative purposes only and are not intended to define or limit the scope of the claims to the extent shown.

[0075] Figure 1AA perspective view of one embodiment of a test device 100 is shown that includes a sensor array cover 102 and a microplate 104. The test device 100 can be used as part of a system for determining the susceptibility of an infectious pathogen to an anti-infective drug. As will be discussed in more detail in the following sections, the system can also include a reader 700 (see Fig. 7A and Figure 7B ), the reader 700 is configured to detect any changes in the solution characteristics of the sample aliquot within the test device 100. The system can analyze the growth or absence of microorganisms in the sample aliquot as part of an antibiotic susceptibility testing (AST) procedure.

[0076] like Figure 1A As shown, the sensor array cover 102 can be configured to cover or cap the microwell plate 104 when placed on top of the microwell plate 104. The microwell plate 104 can include a plurality of holes 105 or microwells. For example, the microwell plate 104 can include 12 holes to 192 holes. As a more specific example, the microwell plate 104 can include 64 holes to 96 holes.

[0077] When the microplate 104 includes 96 wells, the wells 105 can be arranged in an 8×12 well array. In other embodiments, when the microplate 104 includes 48 wells, the wells 105 can be arranged in a 6×8 well array.

[0078] Each well 105 may be designed to receive an aliquot of a sample containing an infectious pathogen. Before the aliquot of the sample is introduced into the well 105, the sample may be diluted.

[0079] In some embodiments, the wells 105 of the microplate 104 may include test wells and control wells. Each test well may contain an anti-infective drug, and the control well may not contain any anti-infective drug (eg, a positive control well).

[0080] For example, when the microplate 104 includes 96 wells, 1 to 20 wells in the microplate 104 can be used as control wells. In other examples, the number of control wells can be more than 20 wells (eg, half of the wells can be control wells).

[0081] The wells 105 of the microplate 104 containing the anti-infective drug may have the anti-infective drug already present in the wells 105 or pre-loaded in the wells 105. In some embodiments, the anti-infective drug in the test wells may be lyophilized or dried. For example, the anti-infective drug in the test wells may be in the form of a lyophilized disk, a granular form, or a powder form.

[0082] In other embodiments, the anti-infective drug within the test well may be in aqueous form.

[0083] In some embodiments, anti-infective drugs may be added, disposed, or otherwise introduced into the wells 105 of the microplate 104 prior to introducing aliquots of the sample into the wells 105 (test wells and control wells).

[0084] In some embodiments, each microplate 104 may contain different types of anti-infective drugs, such that some wells 105 of the microplate 104 are dedicated to specific anti-infective drugs and other wells of the microplate 104 are dedicated to another anti-infective drug. In these embodiments, one microplate 104 may include test wells with 2 to up to 100 anti-infective drugs. In other embodiments, one microplate 104 may include test wells with more than 100 anti-infective drugs (depending on the size of the microplate 104).

[0085] In other embodiments, one microplate 104 may contain only one anti-infective drug, such that all test wells of the microplate 104 are dedicated to the same anti-infective drug.

[0086] The sensor array cover 102 and the microwell plate 104 can be made in part of a polymer material or a thermoplastic material. In some embodiments, a part of the sensor array cover 102, the microwell plate 104, or a combination thereof can also be made of a metallic material, a ceramic, or a combination of these materials with or without a polymer material.

[0087] In certain embodiments, the microplate 104 can be a commercially available or off-the-shelf microplate, such as a microtiter plate or microplate distributed by Thermo Fisher Scientific, Beckman Coulter, VWR International, or Millipore Sigma. As a more specific example, the microplate 104 can be a commercially available or off-the-shelf AST microplate.

[0088] In some embodiments, components of microwell plate 104 and sensor array cover 102 can be made in part from at least one of polystyrene, polypropylene, cyclic olefin copolymer, or other biocompatible polymeric materials.

[0089] The sensor array cover 102 can be made of a material that can withstand sterilization by radiation (eg, gamma rays), heat, or a combination thereof. In some embodiments, the sensor array cover 102 can be packaged separately and provided separately from the microwell plate 104 .

[0090] In some embodiments, the sensor array cover 102 can be made disposable or used only once. In these embodiments, the sensor array cover 102 can be discarded after the testing process is completed.

[0091] Figure 1B A perspective view of the bottom surface of the sensor array cover 102 is shown (bottom surface facing upward). Figure 1A and Figure 1B As shown, the sensor array cover 102 may include a cover top 106 and a flexible substrate 108 coupled to a bottom surface of the cover top 106 .

[0092] The flexible substrate 108 may include a plurality of substrate strips 110 or substrate segments that are partially cut out or otherwise separated from the remainder of the flexible substrate (i.e., the portion of the flexible substrate 108 that is connected to the bottom surface of the sensor array cover 102). The substrate strips 110 may be curled or bent vertically downward relative to the surrounding portions of the flexible substrate 108. Even when the sensor array cover 102 covers or covers the microwell plate 104, the substrate strips 110 may maintain their curled or bent configurations.

[0093] As will be discussed in more detail in the following sections, each substrate strip 110 may include an active electrode 118 and a reference electrode 120 (see FIG. Figure 1H Active electrode 118 and reference electrode 120 may each be connected to electrical contact pads 115 on sensor array cover 102 via one or more conductive traces 122 (see Figure 1H In some embodiments, electrical contact pads 115 can be mounted, attached, or electrically connected to flexible substrate 108 .

[0094] For purposes of the present invention, each substrate strip 110 (including active electrode 118 and reference electrode 120 ) may also be referred to as a sensor cell 112 .

[0095] In some embodiments, the flexible substrate 108 can be at least partially made of a flexible polymer material. For example, the flexible substrate 108 can be partially made of a polyethylene terephthalate (PET) flexible sheet.

[0096] The flexible substrate 108 may also be partially made of a flexible printed circuit board (PCB) material. For example, the flexible substrate 108 may be partially made of polyimide or polyamide.

[0097] In alternative embodiments, the flexible substrate 108 can be made in part from a conductive metal substrate. For example, in these embodiments, the flexible substrate 108 can be made in part from a stainless steel foil.

[0098] In some embodiments, the flexible substrate 108 can be attached to the bottom surface of the cover top 106 via a biocompatible adhesive (eg, a biocompatible polymer adhesive, a cyanoacrylate adhesive, etc.) and fasteners (eg, screws, clips, clasps, etc.).

[0099] Figure 1C to Figure 1E 1 and 2 show a perspective view, a top view, and a bottom view, respectively, of one embodiment of the test device 100 in an assembled configuration. Figure 1C to Figure 1E As shown, when the test device 100 is in the assembled configuration, the sensor array cover 102 can completely cover or fit over the top of the microwell plate 104. Figure 1C As shown, the sides of the sensor array cover 102 can at least partially cover or surround the sides of the microwell plate 104. When the test device 100 is in an assembled configuration, this can allow the test device 100 to have a low-profile or compact profile so that the test device 100 fits within the receiving slot 702 of the reader 700 (see FIG. Fig. 7A , Figure 7B and Figure 8 ).

[0100] Figure 1C and Figure 1D Also shown is a cover top 106 of the sensor array cover 102 that can protect the aliquot of sample within the well 105 from contamination and prevent spilling or inadvertent leaking out of the aliquot of sample.

[0101] The test device 100 in the assembled configuration can have a device length, a device width, and a device height. In some embodiments, the test device 100 in the assembled configuration can have a device length of about 80.0 mm to 160.0 mm (e.g., about 122.5 mm), a device width of about 60.0 mm to 100.0 mm (e.g., 81.0 mm), and a device height of about 10.0 mm to 30.0 mm (e.g., about 20.0 mm).

[0102] As will be discussed in more detail in the following sections, when the sensor array cover 102 covers or covers the microplate 104, each sensor unit 112 (e.g., implemented as a rolled or bent substrate strip 110) can extend into the well 105 of the microplate 104. When the well 105 of the microplate 104 is filled with an aliquot of an inoculum or sample, at least a portion of the sensor unit 112 can be immersed in the aliquot of the inoculum or sample.

[0103] Figure 1FA perspective view of one embodiment of a test device 100 in an assembled configuration is shown, with the side of the test device 100 shown in cross-section for illustration purposes. In this embodiment, the sensor unit 112 is implemented as a rolled or bent substrate strip 110 extending downwardly from the flexible substrate 108. As will be discussed in more detail in the following sections, each substrate strip 110 can include an active electrode 118 and a reference electrode 120 printed, deposited, or plated onto a distal end or distal portion of the substrate strip 110.

[0104] The substrate strips 110 may extend into the wells 105 of the microplate 104. When the wells 105 of the microplate 104 are filled with an aliquot of a sample (e.g., a positive blood culture), at least the distal segment or portion of each substrate strip 110 (which includes the active electrode 118 and the reference electrode 120) may be immersed in the aliquot of the sample.

[0105] The sensor cells 112 may be aligned to match the alignment or arrangement of the wells 105. For example, when the microplate 104 includes 96 wells 105 arranged in an 8×12 array, the sensor array cover 102 may include 96 sensor cells 112 arranged in an 8×12 array.

[0106] In some embodiments, the sensor units 112 may be spaced approximately 6.00 mm to 12.0 mm (approximately 9.00 mm) apart from one another.

[0107] In certain embodiments, the sensor cells 112 can be arranged in such a manner that when the sensor array cover 102 covers or covers the microwell plate 104 , no sensor cells 112 touch or are in contact with the walls of the wells 105 .

[0108] In other embodiments, the sensor units 112 may be arranged in such a manner that when the sensor array cover 102 covers or covers the microwell plate 104 , the sensor units 112 rest against or contact one or more walls of the wells 105 .

[0109] Figure 1F When the sensor units 112 are shown implemented as substrate strips 110, the sensor array cover 102 may include a plurality of posts 114 extending from the bottom surface of the cover top 106. The posts 114 may be configured to abut or press against the substrate strips 110 so that the substrate strips 110 maintain their curled or bent configuration.

[0110] For example, the posts 114 can be angled to allow the posts 114 to abut or press against the base strip 110, thereby ensuring that the base strip 110 maintains its curled or bent configuration. As a more specific example, the posts 114 can be positioned at an oblique angle relative to the bottom surface of the cover top 106.

[0111] The sensor array cover 102 may also include an electrical contact pad 115 disposed at an end, a corner, or an edge of the sensor array cover 102. In some embodiments, the electrical contact pad 115 may be mounted, connected, or electrically connected to the flexible substrate 108.

[0112] For example, the entire electrical contact pad 115 can be exposed through the cover top 106. As a more specific example, the electrical contact pad 115 can be positioned on a ledge or stepped-down portion of the sensor array cover 102.

[0113] In other embodiments, at least a portion of the electrical contact pads 115 may be exposed through one or more openings or apertures defined along the lid top 106 .

[0114] The electrical contact pads 115 may be electronically connected or coupled to the active electrodes 118 and the reference electrodes 120 of the respective sensor cells 112 by a plurality of conductive traces 122. Figure 1H In some embodiments, conductive traces 122 can be routed along a surface or side of flexible substrate 108 (eg, adhered or connected to a side or surface of the bottom surface of cover top 106).

[0115] In other embodiments, the conductive traces 122 may be routed or extended through the flexible substrate 108 or through the body of the cover top 106. For example, when the flexible substrate 108 is made of a PCB material, the conductive traces 122 may be routed or guided through vias or through-holes arranged along the flexible substrate 108.

[0116] The electrical contact pads 115 may be configured to contact or otherwise engage conductive connections within the reader 700 when the entire testing device 100 (in an assembled configuration) is inserted or introduced into the receiving slot 702 of the reader 700 to allow the reader 700 to acquire signals from the sensor unit 112 .

[0117] Figure 1G 1 is a close up view of the posts 114 abutting against the base strip 110 to allow the base strip 110 to maintain its curled or bent configuration. Figure 1GAs shown, the column 114 can be pressed against or pressed against the substrate strip 110 in such a manner that the distal segment 116 of the substrate strip 110 (e.g., the distal segment including the active electrode 118 and the reference electrode 120, see Figure 1H ) is substantially perpendicular to the portion of the flexible substrate 108 connected to the bottom surface of the cover top 106.

[0118] In other embodiments, the posts 114 may abut or press against the base strip 110 in such a manner that the distal end section 116 of the base strip 110 is at an oblique angle (more specifically, 60°) relative to the portion of the flexible base 108 that is connected to the bottom surface of the lid top 106. o to 90 o The angle between them) is placed.

[0119] like Figure 1G As shown, the base strip 110 may be formed by cutting along three sides around the base strip 110 .

[0120] In some embodiments, the base strip 110 may be substantially rectangular in shape. For example, the base strip 110 may be formed as a rectangular sheet or a rectangular strip.

[0121] In other embodiments, the shape of the base strip 110 can be substantially triangular, oval, or semicircular. In further embodiments, the base strip 110 can be shaped as a leaf or leaflet.

[0122] In these and other embodiments, posts 114 may be made of the same non-conductive material (eg, a polymer material) used to make lid top 106 .

[0123] In some embodiments, the post 114 can be a rod or stake extending from the bottom surface of the cover top 106. In further embodiments, the post 114 can be adhered or otherwise secured to the cover top 106.

[0124] In some embodiments, posts 114 may be replaced by protuberances or other types of surface features that protrude from the bottom surface of cover top 106 .

[0125] Although the figures show that the base strip 110 is pressed or pressed into a curled or curved configuration by the column 114, the present invention contemplates that the base strip 110 can also obtain and maintain its curled or curved configuration without the assistance of the column 114 (for example, by pre-forming, pre-setting, pre-training or otherwise manipulating it into such a shape).

[0126] Figure 1His a schematic diagram showing a sensor cell 112 of a sensor array cover 102 including an active electrode 118 and a reference electrode 120 of the sensor cell 112 immersed in an aliquot of a sample in a well 105 of a microplate 104 .

[0127] The wells 105 of the microplate 104 may be sized to accommodate a sufficient amount of sample to allow at least the distal segments 116 of the sensor units 112 to be immersed in the sample when the sensor array cover 102 covers or caps the microplate 104 .

[0128] like Figure 1H As shown, each well 105 of the microplate 104 may include a substantially cylindrical cavity for receiving and holding the sample. In other embodiments, each well 105 of the microplate 104 may include a substantially rectangular parallelepiped cavity, an oval cavity, or a frustoconical cavity.

[0129] As previously described, the sensor units 112 extending from the bottom surface of the sensor array cover 102 may be arranged or positioned so that the sensor units 112 are aligned with the wells 105 of the microplate 104 , with at least the distal segment 116 of each sensor unit 112 extending into the cavity of each well 105 .

[0130] When the sensor unit 112 is implemented as a rolled or bent substrate strip 110 , the distal segment 116 of the sensor unit 112 may refer to a distal segment or a distal portion of the substrate strip 110 .

[0131] like Figure 1H As shown, distal segment 116 of sensor unit 112 may include active electrode 118 and reference electrode 120 disposed on substrate strip 110. As will be discussed in more detail in the following sections, at least one of active electrode 118 and reference electrode 120 may be deposited on substrate strip 110 by screen printing, electroplating, or sputtering.

[0132] The active electrode 118 may include a redox active material. In some embodiments, the redox active material may be a noble metal. For example, the redox active material may be platinum, gold, or a combination or alloy thereof. In other embodiments, the redox active material may be a redox susceptible metal oxide.

[0133] In other embodiments, the redox active material may be a conductive metal oxide, such as iridium oxide, ruthenium oxide, or any combination or alloy of these materials with a noble metal. In yet other embodiments, the redox active material may be a carbon-based electrode.

[0134] The reference electrode 120 may include a reference electrode material. In some embodiments, the reference electrode material may include at least one of silver / silver chloride (Ag / AgCl) and carbon. For example, when the reference electrode material is Ag / AgCl or carbon, the reference electrode material may be screen printed onto the substrate strip 110.

[0135] The reference electrode 120 can be considered a pseudo reference electrode because the reference electrode 120 can operate without a reference buffer. A pseudo reference electrode can be used in these situations because measurements are made by comparing changes in signals rather than comparing absolute values.

[0136] As will be discussed in more detail in subsequent sections, the reference electrode material may be coated with an ion exchange membrane or an ionomer coating.

[0137] In alternative embodiments, the active electrode 118 can be implemented as a post, rod or segment made of a redox active material. In these and other embodiments, the reference electrode 120 can also be implemented as a post, rod or segment coated or covered with a reference electrode material, an ion exchange membrane / ionomer coating, or a combination thereof.

[0138] The active electrode 118 and the reference electrode 120 can also be electrically connected to the electrical contact pads 115 on the sensor array cover 102 through a plurality of conductive traces 122. In some embodiments, the conductive traces 122 can be platinum traces or platinum routing lines. In other embodiments, the conductive traces 122 can be made of other conductive materials such as gold, copper, etc.

[0139] Figure 2A FIG. 1 is a black and white image showing one embodiment of the sensor array cover 102. Figure 2A As shown, the sensor array cover 102 can be made of a transparent polymer material to allow a medical or laboratory professional or technician to view the wells 105 of the microplate 104 and to view the sample aliquots within the wells 105 during the test. In addition, the sensor array cover 102 can be made of a transparent polymer material to allow a medical or laboratory professional or technician to view the sensor unit 112 and ensure that the sensor unit 112 is immersed in the sample aliquot within the well 105.

[0140] As previously mentioned, in some embodiments, sensor array cover 102 can be made in part from at least one of polystyrene, polypropylene, cyclic olefin copolymer, or other biocompatible polymer materials.

[0141] Figure 2B A black and white image showing a close-up of a sensor unit 112 embodied as a substrate strip 110 immersed in a sample aliquot in a well 105 of a microplate 104 .

[0142] Figure 2B The sample shown in is an aliquot of a positive blood culture (PBC) containing an infectious pathogen. The sample can be diluted with a bacterial growth medium such as Mueller Hinton Broth (MHB).

[0143] In addition, if Figure 2B As shown, when the sensor array cover 102 covers or covers the microwell plate 104, the electrodes (such as the active electrode 118 and the reference electrode 120, refer to Figure 1H )'s distal portion or distal segment (implemented as a substrate strip 110) may be immersed in the sample.

[0144] A technical problem faced by the applicant is how to design a low-cost and accurate antimicrobial susceptibility test device that can easily measure multiple samples simultaneously. A technical solution discovered and developed by the applicant is a sensor array cover disclosed herein, which includes a cover top, a flexible substrate connected to the bottom surface of the cover top, and a flexible substrate strip partially cut out from the flexible substrate, which is used as a carrier for an active electrode and a reference electrode disposed on the substrate strip. The sensor array cover can be configured to cover a microplate (including commercially available microplates) containing 12 holes to a maximum of 192 holes. The flexible substrate strip including the active electrode and the reference electrode can extend into the holes of the microplate, and when the sensor array cover covers the microplate, the electrode can be immersed in the sample in the hole. The entire test device (sensor array cover covers the microplate) can then be inserted (for example, as a cartridge or cassette) into the reader to determine whether the infectious pathogen in the sample is susceptible to the anti-infective drug or antibiotic in the hole.

[0145] Figure 3A A portion of a method 300 for creating a screen-printed electrode on a flexible substrate 108 is shown. The method 300 may include covering the flexible substrate 108 with a stencil 302 or mesh. The stencil 302 or mesh may include a stencil pattern or a mesh pattern. The stencil pattern or mesh pattern may match the desired layout or footprint of a material 304 (e.g., electrode material, coating, etc.) to be printed on the flexible substrate 108. A blade 306 (e.g., a rubber scraper) may be used to apply, transfer, or otherwise deposit material 304 through cuts or openings to form a stencil pattern. The blade 306 may be pushed or pulled to apply, transfer, or otherwise direct a thin layer of material 304 onto the flexible substrate 108 in a desired shape or pattern.

[0146] The deposited material 304 may then be dried and / or cured, and in some cases, one or more solvents may be used to ensure that the material 304 properly adheres to the flexible substrate 108. This process may be repeated until enough material 304 adheres to the flexible substrate 108.

[0147] In some embodiments, the reference electrode material of the reference electrode 120 can be screen printed onto the flexible substrate 108. In these and other embodiments, the redox active material of the active electrode 118 can also be screen printed onto the flexible substrate 108.

[0148] In other embodiments, the ion exchange membrane 308 or ionomer coating may also be screen printed onto at least a portion of the flexible substrate 108. For example, as will be discussed in more detail in the following sections, the ion exchange membrane 308 or ionomer coating may be screen printed onto a reference electrode material (e.g., Ag / AgCl or carbon / graphite) that has been screen printed onto the flexible substrate 108.

[0149] As previously described, in some embodiments, the redox active material can be a noble metal, such as platinum, gold, or a combination or alloy thereof. In these embodiments, the redox active material can initially be in the form of an ink or paste (e.g., a platinum or gold ink or paste). The ink or paste (e.g., a platinum or gold ink or paste) can be screen printed onto the flexible substrate 108 using previously disclosed methods (e.g., method 300).

[0150] In other embodiments, the redox active material may be a conductive metal oxide, such as iridium oxide, ruthenium oxide, or any combination or alloy of these materials with a noble metal. In yet other embodiments, the redox active material may be a carbon-based electrode.

[0151] In addition, as previously described, the reference electrode material may include at least one of silver / silver chloride (Ag / AgCl) and carbon. In these embodiments, the reference electrode material may also initially be in the form of an ink or paste (e.g., silver / silver chloride or graphite ink or paste). The ink or paste (e.g., silver / silver chloride or graphite ink or paste) may be screen printed onto another portion of the flexible substrate 108.

[0152] For example, the redox active material may be screen printed onto the distal segment 116 of the substrate strip 110. In this example, the reference electrode material may be screen printed onto the same distal segment 116 of the substrate strip 110, but immediately adjacent or proximate to the redox active material.

[0153] In an alternative embodiment, the Ag / AgCl reference electrode material can also be prepared by chlorinating silver with an electric current in a chlorinating solution.

[0154] Figure 3B A schematic diagram showing that the reference electrode material is disposed on the flexible substrate 108 and the reference electrode material is completely covered by the ion exchange membrane 308 is shown.

[0155] In some embodiments, the ion exchange membrane 308 may be a membrane that blocks certain ions (e.g., Ag). + ions) that may interact with or adversely affect certain microorganisms or other infectious agents. For example, ion exchange membrane 308 may be a sulfonated tetrafluoroethylene fluoride polymer-copolymer such as Nafion™. The sulfonated tetrafluoroethylene fluoride polymer-copolymer may also be referred to as a proton exchange membrane because it may be designed to allow only positively charged ions (e.g., H + ions) flow freely through its polymer layer, but can slow down other ions (e.g., Ag) that may interact with or be harmful to certain microorganisms or other infectious pathogens. + ions) so that they are close to the reference electrode material.

[0156] In other embodiments, the ion exchange membrane 308 can be a polyaromatic polymer anion exchange membrane such as Fumion™. The polyaromatic polymer anion exchange membrane can be designed to allow only anions to pass through its polymer layer. + Some of the harmful ions are cations, so these ions are blocked from entering the sample.

[0157] In some embodiments, the ion exchange membrane 308 can be screen printed onto the flexible substrate 108 and onto the reference electrode material disposed on the flexible substrate 108. In certain embodiments, the reference electrode material can be screen printed onto the flexible substrate 108 first, and the ion exchange membrane 308 can then be screen printed onto the reference electrode material and a portion of the flexible substrate 108.

[0158] A technical problem faced by the applicant is how to prevent harmful ions on the electrode from entering the sample and adversely affecting the growth and metabolism of infectious pathogens. A technical solution discovered and developed by the applicant is to screen-print an ion exchange membrane on a portion of the electrode (e.g., a reference electrode), which can shed such interfering or harmful ions.

[0159] In an alternative embodiment, at least one of the active electrode 118 and the reference electrode 120 can be formed by sputtering deposition. For example, at least one of the redox active material (e.g., platinum) of the active electrode 118 and the reference electrode material of the reference electrode 120 can be sputtered onto the flexible substrate 108 to form such an electrode. Figure 5As discussed in more detail in , the performance of a sensor cell 112 including electrodes formed by sputter deposition was compared to commercially available ORP sensors, and such sputter deposition produced sensor results that were comparable to commercially available ORP sensors.

[0160] In an optional embodiment, at least one of the active electrode 118 and the reference electrode 120 can be formed by electroplating. For example, the redox active material (e.g., platinum and / or gold) of the active electrode 118 and at least one of the reference electrode materials of the reference electrode 120 can be electroplated onto the flexible substrate 108 to form such an electrode. As a more specific example, when the flexible substrate 108 is made of a flexible PCB material (e.g., polyimide / polyamide), the redox active material (e.g., platinum and / or gold) of the active electrode 118 and at least one of the reference electrode materials of the reference electrode 120 can be electroplated onto the flexible PCB material. As will be combined Figure 6 As discussed in greater detail, the performance of two sensor cells 112 including electrodes formed by electroplating are compared to one another to determine the accuracy of such sensors.

[0161] Figure 4A The results obtained using an embodiment of the test device 100 having a screen-printed platinum active electrode 118 and a screen-printed carbon reference electrode 120 are shown. E. coli ) (e.g., E. coli ATCC-25922 strain). An ORP bacterial growth curve obtained using a commercially available ORP sensor is also shown. Before the sample is introduced into the well 105 of the microplate 104, the sample can be diluted using Mueller Hinton broth as a diluent. The commercially available ORP sensor is an ORP sensor distributed by Mettler Toledo.

[0162] like Figure 4A As shown, the performance of the ORP growth curve obtained using the test device 100 including the screen-printed platinum active electrode 118 and the screen-printed carbon reference electrode 120 is comparable to that of commercially available ORP sensors.

[0163] Figure 4B Various ORP bacterial growth curves are shown, which show the growth behavior of susceptible bacteria and resistant bacteria in test wells containing anti-infective drugs and control wells without any anti-infective drugs. ORP bacterial growth curves obtained using commercially available ORP sensors are also shown.

[0164] The anti-infective drug used was ceftriaxone. Ceftriaxone was only present in the test wells, and the control wells did not contain any anti-infective drug. The susceptible bacteria used were the Escherichia coli CDC-650 strain known to be highly susceptible to ceftriaxone. The resistant bacteria used were the Escherichia coli CDC-846 strain known to be resistant to ceftriaxone. The commercially available ORP sensor was an ORP sensor distributed by Mettler Toledo.

[0165] The samples containing susceptible bacteria and resistant bacteria were first diluted using Mueller Hinton broth as a diluent, and then introduced into the test wells and control wells of the microplate 104. The sensor array cover 102 having a substrate strip 110 including a screen-printed platinum active electrode 118 and a screen-printed carbon reference electrode 120 was used as the sensor unit 112. All samples were incubated at 37°C.

[0166] like Figure 4B As shown, the ORP growth curve obtained using the test device 100 including the screen-printed platinum active electrode 118 and the screen-printed carbon reference electrode 120 behaves as expected, and the ORP growth curve obtained using the test device 100 is comparable to the ORP growth curve obtained using the commercially available ORP sensor.

[0167] Figure 5 Shown is an ORP bacterial growth curve obtained using an embodiment of a test device 100 having a sensor cell 112 including a sputter-deposited platinum active electrode 118. Also shown is an ORP bacterial growth curve obtained using a commercially available Mettler Toledo ORP sensor.

[0168] like Figure 5 As shown, the ORP growth curve obtained using the test device 100 having the sensor cell 112 including the sputter-deposited platinum active electrode 118 is comparable to the ORP growth curve obtained using the commercially available ORP sensor.

[0169] Figure 6 An ORP bacterial growth curve is shown obtained using an embodiment of a test device 100 having a sensor unit 112 including an electroplated platinum active electrode 118. The platinum active electrode 118 is electroplated on a flexible substrate 108 made of a flexible PCB material.

[0170] like Figure 6 As shown, the ORP growth curves obtained using the test apparatus 100 having the sensor cell 112 including the electroplated platinum active electrode 118 are comparable to each other and demonstrate the accuracy of the sensor cell 112 .

[0171] Fig. 7A and Figure 7B A perspective view and a front view, respectively, of a reader 700 for receiving a test device 100 (microwell plate 104 covered by sensor array cover 102 ) and detecting any changes in characteristics of a sample solution within wells 105 of the test device 100 .

[0172] The reader 700 may include a plurality of receiving slots 702 for receiving and accommodating the test device 100. In some embodiments, the reader 700 may include four to twelve receiving slots 702 (eg, ten receiving slots 702).

[0173] Each receiving well 702 can accommodate a test device 100 (microwell plate 104 is covered by sensor array cover 102). In certain embodiments, before inserting the test device 100 into the receiving well 702, the test device 100 can be placed in a box or cartridge.

[0174] As previously described, the sensor array cover 102 of the testing device 100 may further include an electrical contact pad 115 located at an end, corner, or edge of the sensor array cover 102. In some embodiments, the electrical contact pad 115 may be mounted, connected, or electrically coupled to the flexible substrate 108.

[0175] For example, the entire electrical contact pad 115 can be exposed through the cover top 106. As a more specific example, the electrical contact pad 115 can be positioned on a ledge or stepped-down portion of the sensor array cover 102.

[0176] In other embodiments, at least a portion of the electrical contact pads 115 may be exposed through one or more openings or apertures defined along the lid top 106 .

[0177] The active electrodes 118 and the reference electrodes 120 of the sensor array cover 102 can be electrically connected to the electrical contact pads 115 by conductive traces 122. The conductive traces 122 can be routed along one side of the flexible substrate 108 or along both sides of the flexible substrate 108. In some embodiments, the conductive traces 122 can pass through the body of the flexible substrate 108 and be routed along one side or both sides of the cover top 106.

[0178] In some embodiments, all reference electrodes 120 of the sensor array cover 102 can be connected by one conductive trace 122. In other embodiments, the reference electrodes 120 of the sensor array cover 102 can be connected by multiple conductive traces 122.

[0179] When the test device 100 (in an assembled configuration) is inserted or introduced into the receiving slot 702 of the reader 700 (e.g., via a box or cartridge), the electrical contact pads 115 can be configured to contact or otherwise engage conductive connections or conductive contacts within the reader 700. For example, when the test device 100 (microwell plate 104 covered by the sensor array cover 102) is pushed, inserted, or otherwise introduced into the receiving slot 702, the conductive connections within the reader 700 can engage or otherwise contact the electrical contact pads 115 of the test device 100.

[0180] Once the test device 100 is inserted into the reader 700 via the receiving slot 702, the reader 700 can automatically begin reading signals from the sensor units 112 of the sensor array cover 102. The reader 700 can be configured to read the signals from the sensor units 112 to detect changes in solution properties of the microbial sample within the well 105 over time. The reader 700 can also be configured to determine the susceptibility of the microorganisms within the sample aliquot to certain anti-infective drugs.

[0181] The reader 700 may also include certain thermal circuits and heating blocks that can be used to incubate aliquots of the sample within the wells 105 of the test device 100. For example, the test device 100 containing the sample aliquots can be incubated at an incubation temperature of about 30° C. to about 40° C. In alternative embodiments, the test device 100 containing the sample aliquots can be incubated external to the reader 700.

[0182] like Fig. 7A and Figure 7B As shown, the reader 700 may also include a display 704. In some embodiments, the display 704 may be an interactive touch screen display. The display 704 may present graphics, messages, or other types of text, or a combination thereof, related to the results of the antimicrobial susceptibility test. In certain embodiments, the display 704 may allow a user to input commands to the reader 700 regarding an upcoming test, an ongoing test, or a completed test.

[0183] Figure 7C A high-level circuit diagram is shown that shows how the reader 700 reads the electrodes (active electrode 118 and reference electrode 120) of the sensor unit 112 (see also Figure 1H and Fig.7D The reader 700 may be used as a high-impedance voltmeter to measure the potential difference between the indicator electrode or active electrode 118 of the sensor cell 112 immersed in a sample and the reference electrode 120 or pseudo-reference electrode of the sensor cell 112 immersed in the same sample.

[0184] The redox potential (ORP) of a sample can refer to the ratio of oxidized molecules to reduced molecules in the sample and is an effective metric for monitoring the growth and metabolism (or lack thereof) of infectious pathogens. As infectious pathogens grow and metabolize, oxygen and other electron donors are consumed. This results in a higher ratio of reduced molecules, making the ORP more negative.

[0185] To measure the ORP of the medium, an electrode material that is redox-sensitive but inert (e.g., made of a noble metal such as platinum or gold) can be used as the active electrode 118. The reference electrode 120 can be a silver / silver chloride pseudo-reference electrode or a carbon reference electrode. The reference electrode 120 does not respond to redox changes in the sample, while reduced molecules (molecules with excess electrons) easily lose electrons at the active electrode 118, resulting in the accumulation of negative charges. Therefore, as the growth / metabolism of infectious pathogens proceeds, the ORP in the sample becomes more negative. In the absence of infectious pathogen growth / metabolism, the ORP of the sample remains constant during the measurement.

[0186] Fig.7D Schematic diagram showing some of the steps taken by the electronics of the reader 700 to process the signals obtained from the sensor unit 112. Fig.7D As shown, the analog signals read from each sensor unit 112 may first be buffered by a buffer circuit within the reader 700. The buffered signals may then be provided as inputs to an analog multiplexer (MUX) within the reader 700. The analog multiplexer may iterate over each sensor unit 112. The analog signals from the multiplexer may then be converted to digital signals, which may be analyzed by a microcontroller within the reader 700 to determine whether the infectious agent is susceptible (showing no signs of growth), moderately susceptible (showing some signs of growth), or resistant (showing signs of growth).

[0187] Figure 8 The various steps of one embodiment of a method for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs are shown. The method can utilize the devices, apparatuses, and systems disclosed herein, including a test device 100 including a sensor array cover 102 and a reader 700.

[0188] The method may include diluting the sample with a diluent to a dilution ratio of about 1:1 to about 1:10,000.

[0189] In some embodiments, the sample can be obtained from an individual or patient. In other embodiments, the sample can be a biological sample, an environmental sample, or a food sample.

[0190] When the sample is an environmental sample, the sample may be obtained from a stream, river, lake, ocean, contaminated site, quarantine area, emergency area, or some combination thereof.

[0191] When the sample is a food sample, the sample may be obtained from a food preparation facility, a dining establishment, a waste treatment facility, or a combination thereof.

[0192] When the sample is obtained from a patient or individual, the sample may include at least one of a bodily fluid of the individual or patient or a resuspended swab obtained from the individual or patient.

[0193] In some embodiments, the individual or patient can be a human individual or patient.

[0194] In other embodiments, the individual or patient can be a non-human animal individual or patient.

[0195] In some embodiments, the sample can include blood, urine, serum, plasma, saliva, sputum, semen, breast milk, joint fluid, spinal fluid (e.g., cerebrospinal fluid), wound discharge, mucus, fluid accompanying stool, vaginal secretions, synovial fluid, pleural effusion, peritoneal fluid, pericardial fluid, amniotic fluid, or a combination thereof.

[0196] In some embodiments, the sample may include or refer to a bacterial culture from at least one of a sample obtained from an individual or patient, a biological sample, an environmental sample, and a food sample. For example, the sample may include or refer to a bacterial culture or a resuspended bacterial culture from a body fluid or swab obtained from an individual or patient.

[0197] As a more specific example, a sample may include or refer to a bacterial culture derived from blood or other bodily fluid obtained from a patient or individual that has tested positive for microbial growth. When the sample is a bacterial culture derived from blood, the sample may be or be referred to as a positive blood culture (PBC).

[0198] PBC can be a bacterial culture derived from blood extracted from a patient or individual who has been detected to be positive for microbial growth. For example, a patient may show symptoms of sepsis (e.g., high fever, chills, etc.), and blood (e.g., 5 mL to 10 mL) can be drawn from the patient and transferred to a commercial blood culture container or vessel containing a bacterial growth medium (e.g., 30 mL to 40 mL of growth medium). The blood culture container or vessel is then incubated at 35°C ± 2°C to allow bacteria to proliferate. If the patient's blood is contaminated with bacteria, the bacteria will replicate in the container / vessel, and the blood culture system or device can determine that the bacterial growth test of the sample is "positive". Depending on the type and growth rate of the pathogen, the blood culture may be positive within 7 hours to 3 days. Such PBC can then be used for further downstream testing (e.g., antimicrobial susceptibility testing) using the devices, equipment, systems, and methods disclosed herein.

[0199] In some embodiments, the sample can include bacteria. In these embodiments, the bacteria can be selected from the genus consisting of Acinetobacter, Acetobacter, Actinomyces, Aerococcus, Aeromonas, Agrobacterium, Anaplasma, Azorhizobium, Azotobacter, Bacillus, Bacteriodes, Bartonella, ), Bordetella, Borrelia, Brucella, Burkholderia, Calymmatobacterium, Campylobacter, Chlamydia, Chlamydophila, Citrobacter, Clostridium, Corynebacterium, Coxiella, Ehrli chia), Enterobacter, Enterococcus, Escherichia, Francisella, Fusobacterium, Gardnerella, Haemophilus, Helicobacter, Klebsiella, Lactobacillus, Legionella, Listeria, Meth anobacterium), Microbacterium, Micrococcus, Morganella, Moraxella, Mycobacterium, Mycoplasma, Neisseria, Pandoraea, Pasteurella, Peptostreptococcus, Porphyromonas, Prevotella,Proteus, Providencia, Pseudomonas, Ralstonia, Raoultella, Rhizobium, Rickettsia, Rochalimaea, Rothia, Salmonella, Serratia, Shewanella, Shigella, Spirillum, Staphylococcus, Strenotrophomonas, Streptococcus, Streptomyces, Treponema, Vibrio, Wolbachia, Yersinia.

[0200] More specifically, the bacterium can be a species selected from the group consisting of: Acinetobacter baumannii (A. Baumannii), Actinomycetes, Actinomycetes, Actinomyces (including but not limited to Actinomyces ilei and Actinomyces naeslundii), Aeromonas (including but not limited to Aeromonas hydrophila, Aeromonas versii sobriae (Aeromonas sobriae) and Aeromonas caviae), Anaplasma phagocytophilum, Alcaligenes xylosoxidans, Actinomycetemcomitans, Bacillus (including but not limited to Bacillus anthracis, Bacillus cereus, Bacillus subtilis, Bacillus thuringiensis and Bacillus thermophilus), Bacteroides (including but not limited to Bacteroides fragilis), Bartonella (including but not limited to Bartonella bacilliformis and Bartonella henselae), Bifidobacterium, Bordetella (including but not limited to Bordetella pertussis, Bordetella parapertussis and Bordetella bronchitis), Borrelia (including but not limited to Borrelia relapsing fever and Borrelia burgdorferi), Brucella (including but not limited to Brucella abortus, Brucella canis, Brucella malta and Brucella suis), Burkholderia (including but not limited to Burkholderia pseudomallei and Burkholderia cepacia), Campylobacter (including but not limited to Campylobacter jejuni, Campylobacter coli, Campylobacter gull and Campylobacter fetus), Capnocytophaga, Cardiomycobacter, Chlamydia trachomatis, Chlamydia pneumoniae, Chlamydia psittaci, Citrobacter, Coxiella burnetii (including but not limited to burnetii), Corynebacterium (including but not limited to Corynebacterium diphtheriae, Corynebacterium jejuni and Corynebacterium), Clostridium (including but not limited to Clostridium perfringens, Clostridium difficile, Clostridium botulinum and Clostridium tetani), Eikenella corrosi, Enterobacter (including but not limited to Enterobacter aerogenes, Enterobacter agglomerans, Enterobacter cloacae) and Escherichia coli (including opportunistic Escherichia coli (E.coli), including but not limited to enterotoxigenic Escherichia coli, enteroinvasive Escherichia coli, enteropathogenic Escherichia coli, enterohemorrhagic Escherichia coli, enteroaggregative Escherichia coli, and uropathogenic Escherichia coli), Enterococcus (including but not limited to Enterococcus faecalis and Enterococcus faecium), Ehrlichia (including but not limited to Ehrlichia chaffeensis and Ehrlichia canis), Erysipelothrix rhusiopathiae, Eubacterium tularensis, Francisella tularensis, Fusobacterium nucleatum, Gardnerella vaginalis, Gemini cocci, Haemophilus (including but not limited to Haemophilus influenzae, Haemophilus ducreyi, Haemophilus aegypti, Haemophilus parainfluenzae, Haemophilus haemolyticus, and Haemophilus parahaemolyticus), Helicobacter (including but not limited to Helicobacter pylori, Helicobacter homosexualus, and Helicobacter fennellus), Kingella kingii, Klebsiella (including but not limited to Klebsiella pneumoniae, Klebsiella granulomata, granulomatis and Klebsiella oxytoca), Lactobacillus spp., Listeria monocytogenes, Leptospira interrogans, Legionella pneumophila, Leptospira interrogans, Peptostreptococcus spp., Moraxella catarrhalis, Morganella spp., Mobiluncus spp., Micrococcus spp., Mycobacterium spp. (including but not limited to Mycobacterium leprae, Mycobacterium tuberculosis, Mycobacterium intracellulare, Mycobacterium avium, Mycobacterium bovis and Mycobacterium marinum), Mycoplasma spp. (including but not limited to Mycoplasma pneumoniae, Mycoplasma hominis and Mycoplasma genitalium), Nocardia spp. (including but not limited to Nocardia asteroides, Nocardia gelsenkirchen and Nocardia spp.), cyriacigeorgica and Nocardia brasiliensis), Neisseria (including but not limited to Neisseria gonorrhoeae and Neisseria meningitidis), Pasteurella multocida, Pseudomonas shigellae-like, Prevotella, Porphyromonas, Prevotella melaninogenicus and Proteus (including but not limited to Proteus vulgaris and Proteus mirabilis), Providencia (including but not limited to Providencia alcaligenes, Providencia rettgeri and Providencia stuartii), Pseudomonas aeruginosa, Propionibacterium acnes, Rhodococcus equi, Rickettsia (including but not limited to Rickettsia rickettsii, Rickettsia spiderii and Rickettsia prowazekii), Orientia tsutsugamushi (formerly known as Rickettsia tsutsugamushi) tsutsugamushi and Rickettsia typhi), Rhodococcus, Stenotrophomonas maltophilia, Salmonella (including but not limited to Salmonella enterica, Salmonella typhi, Salmonella paratyphi, Salmonella enteritidis, Salmonella choleraesuis and Salmonella typhimurium), Serratia (including but not limited to Serratia marcescens (S.marcesans and Serratia liquefaciens), Shigella (including but not limited to Shigella dysenteriae, Shigella flexneri, Shigella boydii and Shigella sonnei), Staphylococcus (including but not limited to Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus saprophyticus), Streptococcus (including but not limited to Streptococcus pneumoniae (e.g., chloramphenicol-resistant serotype 4 Streptococcus pneumoniae, spectinomycin-resistant serotype 6B Streptococcus pneumoniae, streptomycin-resistant serotype 9V Streptococcus pneumoniae, erythromycin-resistant serotype 14 Streptococcus pneumoniae, optoxine-resistant serotype 14 Streptococcus pneumoniae, rifampicin-resistant serotype 18C Streptococcus pneumoniae, tetracycline-resistant serotype 19F Streptococcus pneumoniae, penicillin-resistant serotype 19F Streptococcus pneumoniae and trimethoprim-resistant serotype 23F Streptococcus pneumoniae, chloramphenicol-resistant resistant to spectinomycin serotype 4 Streptococcus pneumoniae, spectinomycin serotype 6B Streptococcus pneumoniae, streptomycin serotype 9V Streptococcus pneumoniae, optoxine serotype 14 Streptococcus pneumoniae, rifampicin serotype 18C Streptococcus pneumoniae, penicillin serotype 19F Streptococcus pneumoniae, or trimethoprim serotype 23F Streptococcus pneumoniae), Streptococcus agalactiae, Streptococcus mutans, Streptococcus pyogenes, group A Streptococcus, Streptococcus pyogenes, group B Streptococcus, Streptococcus agalactiae, group C Streptococcus, Streptococcus anginosus, Streptococcus equi, group D Streptococcus, Streptococcus bovis, group F Streptococcus, Streptococcus anginosus, and group G Streptococcus), Spirillum, Streptobacillus moniliformis, Treponema (including but not limited to Treponema pintacens, Treponema tenuissima, Treponema pallidum, Treponema beyeremi), and Tropheryma whipplei. whipplei), Ureaplasma urealyticum, Veillonella, Vibrio (including but not limited to Vibrio cholerae, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio parahaemolyticus, Vibrio vulnificus, Vibrio alginolyticus, Vibrio mimicus, Vibrio holmenii, Vibrio fluvii, Vibrio merini, Vibrio mermaidii, and Vibrio furnis), Xanthomonas maltophilia, and Yersinia (including but not limited to Yersinia enterocolitica, Yersinia pestis, and Yersinia pseudotuberculosis).

[0201] In embodiments where the sample contains bacteria, the anti-infective drug may include or be a bacteriostatic anti-infective drug, a bactericidal anti-infective drug, or a combination thereof.

[0202] In certain embodiments, antibacterial anti-infective drugs may include β-lactams (including but not limited to penicillins (e.g., ampicillin, amoxicillin, flucloxacillin, penicillin, amoxicillin / clavulanic acid and ticarcillin / clavulanic acid) and monobactams (e.g., aztreonam)), β-lactams and β-lactam inhibitor combinations (including but not limited to piperacillin-tazobactam and ampicillin-sulbactam), aminoglycosides (including but not limited to amikacin, gentamicin, kanamycin, neomycin, netilmicin, paromomycin, streptomycin, spectinomycin and tobramycin), ansamycins (including but not limited to rifaximin) , carbapenems (including but not limited to ertapenem, doripenem, imipenem and meropenem), cephalosporins (including but not limited to ceftaroline, cefepime, ceftazidime, ceftriaxone, cefdroxil, cephalothin, cefazolin, cefalexin, cefaclor, cefprozil, fecluroxime, cefixime, cefdinir, cefditoren, cefotaxime, cefpodoxime, ceftibuten and ceftobiprole), chloramphenicols, glycopeptides (including but not limited to vancomycin, teicoplanin, telavancin, dalbavancin and oritavancin), folate synthesis inhibitors (including but not limited to trimethoprim-sulfonamide oxazolidinones (including but not limited to linezolid, bosizolid, ranizolid and torazolid), quinolones (including but not limited to enoxacin, gatifloxacin, gemifloxacin, levofloxacin, lomefloxacin, moxifloxacin, nalidixic acid, norfloxacin, chloramphenicol ... , trovafloxacin, grefloxacin, sparfloxacin and temafloxacin), rifampicins, streptogramins, sulfonamides (including but not limited to mafenide, sulfacetamide, sulfadiazine, sulfadimethoxine, sulfamethoxazole, sulfamethoxazole, sulfasalazine and sulfisoxazole), tetracyclines (including but not limited to oxycycline, minocycline, demeclocycline, doxycycline, oxytetracycline and tetracycline), polypeptides (including but not limited to bacitracin, polymyxin B, colistin and cyclic lipopeptides (such as daptomycin)), bacteriophages, or combinations or derivatives thereof.

[0203] In other embodiments, the anti-infective drug may include clofazimine, ethambutol, isoniazid, rifampicin, arsphenamine, chloramphenicol, fosfomycin, metronidazole, tigecycline, trimethoprim, or combinations or derivatives thereof.

[0204] In embodiments where the sample may contain fungi, the anti-infective drug may include an antifungal agent. For example, the antifungal agent may include amphotericin B, anidulafungin, caspofungin, fluconazole, flucytosine, itraconazole, ketoconazole, micafungin, posaconazole, ravuconazole, voriconazole, or combinations or derivatives thereof.

[0205] As previously described, in some embodiments, the anti-infective drug may be pre-added or otherwise present in the test wells of the microplate 104. In other embodiments, the anti-infective drug may be added or otherwise introduced into the test wells of the microplate 104 before the aliquot of the sample is added to the wells 105 of the microplate.

[0206] In some embodiments, the anti-infective drug in the test well can be lyophilized or dried. In other embodiments, the anti-infective drug in the test well can be in aqueous form.

[0207] The method may also include introducing an aliquot of the sample containing the infectious agent into the wells 105 of the microplate 104. As previously described, the wells 105 may include test wells and control wells (eg, positive control wells).

[0208] In some embodiments, the microplate 104 may contain multiple anti-infective drugs, such that certain wells 105 of the microplate 104 are dedicated to certain anti-infective drugs. In other embodiments, the microplate 104 may contain only one anti-infective drug.

[0209] The method may also include placing the sensor array cover 102 on top of the microplate 104 containing the sample aliquot, or covering the microplate 104 with the sensor array cover 102 .

[0210] As previously described, the sensor array cover 102 can include a plurality of sensor units 112 extending from a bottom surface of the sensor array cover 102. Each sensor unit 112 can be configured to extend into a well 105 of a microplate 104 such that the sensor unit 112 is at least partially immersed in an aliquot of a sample within the well 105 when the sensor array cover 102 is placed on top of or covering the microplate 104.

[0211] The method may also include inserting or otherwise loading the microwell plate 104 covered by the sensor array cover 102 into the reader 700. The reader 700 may include conductive contacts or conductive connections for electrically contacting the active electrodes 118 and the reference electrodes 120 of the sensor cells 112.

[0212] In some embodiments, the assembled test device 100 within the reader 700 (microwell plate 104 covered by sensor array cover 102 ) can be incubated within the reader 700 at an incubation temperature of about 30° C. to about 40° C.

[0213] The method may also include determining the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in solution characteristics of the sample aliquots in the test wells containing the anti-infective drug and any changes in solution characteristics of the sample aliquots in the control wells over a period of time.

[0214] In some embodiments, the reader 700 can monitor microbial growth within the wells 105 by tracking or monitoring changes (or lack of changes) in solution properties of the sample aliquots within the test wells and control wells. The reader 700 can then compare any changes in solution properties of the sample aliquots within the test wells with any changes in solution properties of the sample aliquots within the control wells to determine the susceptibility of the infectious pathogen to anti-infective drugs.

[0215] The reader 700 and one or more computing devices in communication with the reader 700 can analyze the signals obtained from the plurality of sensor units 112 of the testing device 100 and provide information about the susceptibility of the infectious pathogen to anti-infective drugs (e.g., susceptibility level) and information about the minimum inhibitory concentration (MIC).

[0216] In some embodiments, the results of the test process (e.g., MIC and susceptibility level) can be obtained and displayed or otherwise communicated between 4 hours and up to 10 hours. In certain embodiments, the results of the test process (e.g., MIC and susceptibility level) can be obtained and displayed or otherwise communicated between two hours and four hours.

[0217] Fig.9A is a table showing the performance results for 293 Gram-negative artificial PBCs in the presence of several antibiotics. The antibiotics include amikacin (AMK), ceftriaxone (CRO), aztreonam (ATM), cefazolin (CFZ), imipenem (IPM), piperacillin-tazobactam (TZP), trimethoprim-sulfamethoxazole (SXT).

[0218] Artificial PBCs were prepared in standard aerobic bottles using 293 frozen Gram-negative isolates obtained from the Centers for Disease Control (CDC) and various hospitals. The 293 artificial PBCs were processed within five hours of the flag time and tested in singlet.

[0219] Gram-negative isolates included Escherichia coli, Klebsiella spp., Enterobacter spp., Pseudomonas aeruginosa, Acinetobacter baumannii, Serratia marcescens, Proteus spp., and Citrobacter spp.

[0220] All artificial PBCs are diluted with Mueller Hinton broth (MHB), and aliquots of the diluted samples are transferred to wells 105 of several microplates 104 (e.g., 96-well microplates 104). The test wells of the microplates 104 contain the seven clinically significant antibiotics mentioned above in lyophilized form.

[0221] The sensor array cover 102 is placed on top of the microplate 104 containing the diluted PBC. The entire test device 100 is then loaded into the reader 700 for antimicrobial susceptibility testing. Results for some antibiotics can be obtained in as little as four hours (see Fig. 9C ). The sensor array cover 102 includes a sensor cell 112 that includes a screen-printed platinum active electrode 118 and a screen-printed Ag / AgCl reference electrode 120 .

[0222] Clinical and Laboratory Standards Institute (CLSI) interpretations were applied (reference CLSI, Performance Standards for Antimicrobial Susceptibility Testing, 30th edition, CLSI Supplement M100), and all MIC results were compared to MICs determined using a standard broth microdilution method. Broth microdilutions were prepared using a 0.5 McFarland standard sample diluted according to the manufacturer's recommended guidelines. Broth microdilution results were read manually after a 21-hour incubation time.

[0223] like Fig.9A As shown, basic consistency (EA), classification consistency (CA), minor difference (mD) rate, large difference (MD) rate, and very large difference (VMD) rate were calculated according to FDA guidelines. The overall EA produced by the test was 98.1%, and the CA was 95.2% (mD rate was 4.0%, MD rate was 1.1%, and VMD rate was 0.4%). These results easily met the standards set by the FDA, that is, EA and CA were both >90%, MD<3%, and VMD<3%. This shows that compared to the methods currently considered to be the gold standard in the field, the systems, devices, and methods disclosed herein can produce accurate AST results.

[0224] Fig. 9Bis a table showing the performance results of 34 prospective Gram-negative PBCs in the presence of several antibiotics. The antibiotics include AMK, CRO, ATM, CFZ, IPM, TZP, and SXT.

[0225] The expected PBCs were obtained from a local hospital. 34 expected PBCs were processed within 12 h of labeling time and underwent triplet testing.

[0226] The bacteria identified included Escherichia coli, Klebsiella spp., Enterobacter spp., Pseudomonas aeruginosa, Serratia marcescens, and Proteus spp.

[0227] All expected PBCs are diluted with Mueller Hinton broth (MHB), and then aliquots of the diluted samples are transferred to wells 105 of several microplates 104 (eg, 96-well microplates 104). The test wells contain the seven clinically significant antibiotics mentioned above in lyophilized form.

[0228] The sensor array cover 102 is placed on top of the microplate 104 containing the diluted PBC. The entire test device 100 is then loaded into the reader 700 for antimicrobial susceptibility testing. Test results for some antibiotics can be obtained in as little as four hours.

[0229] Clinical and Laboratory Standards Institute (CLSI) interpretations were applied (reference CLSI, Performance Standards for Antimicrobial Susceptibility Testing, 30th edition, CLSI Supplement M100), and all MIC results were compared to MICs determined using a standard broth microdilution method. Broth microdilutions were prepared using a 0.5 McFarland standard sample diluted according to the manufacturer's recommended guidelines. Broth microdilution results were read manually after a 21-hour incubation time.

[0230] like Fig. 9B As shown, the test produced an overall EA of 96.5% and a CA of 95.0% (mD rate of 3.0%, MD rate of 2.5% and VMD rate of 0.0%). These results easily meet the standards set by the FDA, namely, EA and CA are both >90%, MD<3% and VMD<3%. This shows that the systems, devices and methods disclosed herein can produce accurate AST results compared to the methods currently considered to be the gold standard in the field.

[0231] Fig. 9C is shown with Fig.9ARelated graphs of time-to-result (TTR) (in hours) for the above Gram-negative artificial PBC. Fig. 9C As shown, the TTR for gram-negative PBC with cefazolin (CFZ) and ceftriaxone (CRO) is close to 4 hours, while the TTR for other anti-infective drugs ranges from about 5 hours to 9 hours. Since results obtained using the standard broth microdilution method take up to 21 hours, Fig. 9C It is demonstrated that the systems, devices, and methods disclosed herein can produce accurate AST results in a much shorter time than standard methods.

[0232] Fig. 10A A side cross-sectional view of another embodiment of a testing device 1000 is shown that includes a sensor array cover 1002 that includes sensor cells 1012 having active electrodes 1018 implemented as posts 1001 extending into wells 1005 of a microplate 1004 .

[0233] Fig. 10A The test apparatus 1000 shown in FIG. Figures 1A to 1H 100, except that each sensor unit 1012 includes an active electrode 1018 made of a pile 1001 coated with a redox active material. In some embodiments, the redox active material can be a noble metal. For example, the redox active material can be partially made of a noble metal (e.g., platinum, gold, or a combination or alloy thereof). As a more specific example, the active electrode 1018 can be implemented as a pile 1001 coated with platinum.

[0234] In other embodiments, the redox active material may be a conductive metal oxide, such as iridium oxide, ruthenium oxide, or any combination or alloy of these materials with a noble metal.

[0235] The test device 1000 can also be used as part of a system for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs. For example, the entire test device 1000 (including the microplate 1004 covered by the sensor array cover 1002) can be inserted or otherwise introduced into the receiving slot 702 of the reader 700 (see Fig. 7A and Figure 7B ). As part of an antibiotic susceptibility testing (AST) procedure, the system can analyze the growth or absence of microorganisms in a sample aliquot within well 1005.

[0236] like Fig. 10AAs shown, the sensor array cover 1002 can be configured to cover or cap the microwell plate 1004 when placed on top of the microwell plate 1004. The microwell plate 1004 can include a plurality of holes 1005 or microwells. For example, the microwell plate 1004 can include 12 holes to 192 holes. As a more specific example, the microwell plate 1004 can include 64 holes to 96 holes.

[0237] Each well 1005 may be designed to receive a sample containing an infectious agent. The sample may be diluted before an aliquot of the sample is introduced into the well 1005. In certain embodiments, the microplate 104 may be a commercially available or off-the-shelf microplate or microtiter plate.

[0238] The sensor array cover 1002 may include a cover top 1006 and a flexible substrate 1008 connected to the bottom surface of the cover top 1006 .

[0239] exist Fig. 10A In the embodiment of the test device 1000 shown, the flexible substrate 1008 can include a plurality of substrate strips 1010 or substrate segments (i.e., the portion of the flexible substrate 1008 that is connected to the bottom surface of the sensor array cover 1002) that are partially cut out or otherwise separated from the remaining portion of the flexible substrate 1008. The substrate strips 1010 can be curled or bent vertically downward relative to the surrounding portion of the flexible substrate 1008. The substrate strips 1010 can maintain their curled or bent configuration even when the sensor array cover 1002 covers or covers the microwell plate 1004. In this embodiment, the substrate strips 1010 can include a reference electrode 1020 disposed on the substrate strips 1010. For example, the reference electrode 1020 can be screen printed, sputter deposited, or electroplated onto the substrate strips 1010.

[0240] The reference electrode 1020 may include a reference electrode material. In some embodiments, the reference electrode material may include at least one of silver / silver chloride (Ag / AgCl) and carbon. For example, when the reference electrode material is Ag / AgCl or carbon, the reference electrode material may be screen printed onto the substrate strip 1010.

[0241] The reference electrode 1020 can be considered a pseudo-reference electrode because the reference electrode 1020 can operate without the need for a reference buffer.

[0242] The reference electrode material may be coated with an ion exchange membrane or ionomer coating. In some embodiments, the ion exchange membrane may be a sulfonated tetrafluoroethylene based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane. The ion exchange membrane may be screen printed onto the reference electrode material and a portion of the substrate strip 1010.

[0243] The sensor array cover 1002 may also include a plurality of active electrodes 1018 implemented as posts 1001 extending from the bottom surface of the sensor array cover 1002. The posts 1001 may be coated with a redox active material (eg, platinum) so that the posts 1001 may function as active electrodes 1018.

[0244] In some embodiments, the posts 1001 can be partially connected to the flexible substrate 1008. The posts 1001 can also be connected to the cover top 1006 of the sensor array cover 1002.

[0245] The active electrode 1018 (coated post 1001) and the reference electrode 1020 can be connected to electrical contact pads on the sensor array cover 1002 via one or more conductive traces. The electrical contact pads can be mounted, connected or electrically connected to the flexible substrate 1008.

[0246] The contact pads of the sensor array cover 1002 can be electronically connected or coupled to the active electrode 1018 (e.g., the coated post 1001) and the reference electrode 1020 by a plurality of conductive traces. In some embodiments, the conductive traces can be routed along a surface or side of the flexible substrate 1008 (e.g., adhered or coupled to a side or surface of the bottom surface of the cover top 1006). When the entire test device 1000 (in an assembled configuration) is inserted or introduced into the receiving slot 702 of the reader 700, the contact pads can be configured to contact or otherwise engage the conductive connections within the reader 700 to allow the reader 700 to obtain signals from the active electrode 1018 and the reference electrode 1020.

[0247] In some embodiments, the flexible substrate 1008 can be at least partially made of a flexible polymer material. For example, the flexible substrate 1008 can be partially made of a flexible sheet of polyethylene terephthalate (PET).

[0248] The flexible substrate 1008 may also be partially made of a flexible printed circuit board (PCB) material. For example, the flexible substrate 1008 may be partially made of polyimide or polyamide.

[0249] In alternative embodiments, the flexible substrate 1008 can be made in part from a conductive metal substrate. For example, in these embodiments, the flexible substrate 1008 can be made in part from a stainless steel foil.

[0250] In some embodiments, the flexible substrate 1008 can be connected to the bottom surface of the cover top 1006 via a biocompatible adhesive (eg, a biocompatible polymer adhesive, a cyanoacrylate adhesive, etc.) and fasteners (eg, screws, clips, clasps, etc.).

[0251] When the testing device 1000 is in an assembled configuration, the sensor array cover 1002 can completely cover or fit on top of the microwell plate 1004. The sensor array cover 1002 including the cover top 1006 can protect the sample aliquots within the wells 1005 from contamination and prevent the sample aliquots from spilling or inadvertently leaking.

[0252] For purposes of the present invention, sensor unit 1012 may refer to a substrate strip 1010 including a reference electrode 1020 and an active electrode 1018 , which is implemented as a coating peg 1001 located in the same hole 1005 as the substrate strip 1010 .

[0253] In other embodiments, both the active electrode 1018 and the reference electrode 1020 can be implemented as coated posts. In these embodiments, the active electrode 1018 can be a post coated with a redox active material (e.g., platinum or gold), and the reference electrode 1020 can be a post coated with a reference electrode material or a post made of a reference electrode material. The post used as a reference electrode can be further coated with an ion exchange membrane or an ion exchange coating or an ionomer coating.

[0254] When the sensor array cover 1002 covers or covers the microplate 1004, the individual sensor units 1012 (e.g., implemented as a rolled or bent substrate strip 110) can extend into the wells 1005 of the microplate 1004. When the wells 1005 of the microplate 1004 are filled with an aliquot of an inoculum or sample, at least a portion of the sensor units 1012 can be immersed in the aliquot of the inoculum or sample.

[0255] The sensor cells 1012 may be aligned to match the alignment or arrangement of the wells 1005. For example, when the microplate 1004 includes 96 wells 1005 arranged in an 8×12 array, the sensor array cover 1002 may include 96 sensor cells 1012 arranged in an 8×12 array.

[0256] Fig. 10B is a black and white image showing a platinum coated post 1001 used as an active electrode 1018 of a sensor array cover 1002. Fig. 10B As shown, the pile 1001 may be formed as a miniature cylindrical rod.

[0257] In some embodiments, the platinum-coated post 1001 can be connected to the flexible substrate 1008 by a biocompatible adhesive. In other embodiments, the platinum-coated post 1001 can be connected to the flexible substrate 1008 by a mechanical fastening or fixing mechanism (e.g., threaded connection, interference fit, etc.).

[0258] The following clauses define certain aspects and embodiments of the invention:

[0259] Item 1: A sensor array cover comprising: a cover top; a flexible substrate connected to the bottom surface of the cover top, wherein the flexible substrate comprises a plurality of substrate strips or substrate segments partially cut out from a remaining portion of the flexible substrate, wherein at least one substrate strip or substrate segment of the flexible substrate is curled or bent vertically downward relative to a surrounding portion of the flexible substrate; an active electrode disposed on each substrate strip or substrate segment that is curled or bent vertically downward; and a reference electrode disposed on each substrate strip or substrate segment that is curled or bent vertically downward.

[0260] Item 2: The sensor array cover of Item 1, wherein the active electrode comprises a redox active material.

[0261] Item 3: The sensor array cover of item 2, wherein the redox active material is a noble metal.

[0262] Item 4: The sensor array cover of Item 2, wherein the redox active material is a metal oxide.

[0263] Article 5: The sensor array cover of Article 1, wherein the reference electrode comprises a reference electrode substance.

[0264] Item 6: The sensor array cover of Item 5, wherein the reference electrode material comprises at least one of silver / silver chloride (Ag / AgCl) and carbon.

[0265] Item 7: A sensor array cover according to Item 6, wherein the reference electrode material is coated or covered by an ion exchange membrane.

[0266] Item 8: The sensor array cover of Item 7, wherein the ion exchange membrane is a sulfonated tetrafluoroethylene based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane.

[0267] Item 9: The sensor array cover of Item 1, wherein the cover top includes posts extending from a bottom surface of the cover top, wherein the posts are configured to abut or press against a substrate strip or substrate segment so that the substrate strip or substrate segment maintains its curled or bent configuration.

[0268] Item 10: The sensor array cover of Item 9, wherein at least one substrate strip or substrate segment is abutted or pressed against by at least one post such that a portion of the substrate strip or substrate segment is substantially perpendicular to a portion of the flexible substrate connected to the top of the cover.

[0269] Clause 11: The sensor array cover of clause 1, wherein the flexible substrate is made in part of a flexible polymer material.

[0270] Clause 12: The sensor array cover of Clause 11, wherein the flexible polymer material is made in part from polyethylene terephthalate (PET).

[0271] Clause 13: The sensor array cover of Clause 11, wherein the flexible polymer material is a flexible printed circuit board (PCB) material.

[0272] Clause 14: The sensor array cover of clause 13, wherein the flexible PCB material is polyimide.

[0273] Clause 15: The sensor array cover of clause 1, wherein the flexible substrate is made in part from a conductive metal substrate.

[0274] Item 16: The sensor array cover of Item 15, wherein the conductive metal substrate is a stainless steel foil.

[0275] Clause 17: The sensor array cover of clause 1, wherein the cover top is made in part from at least one of polystyrene, polypropylene, and cyclic olefin copolymer.

[0276] Item 18: The sensor array cover of Item 1, wherein at least one of the active electrode and the reference electrode is a screen printed electrode (SPE), such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is screen printed onto a flexible substrate.

[0277] Item 19: The sensor array cover of Item 1, wherein at least one of the active electrode and the reference electrode is a plated electrode such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is plated onto the flexible substrate.

[0278] Item 20: The sensor array cover of Item 1, wherein at least one of the active electrode and the reference electrode is a sputter deposited electrode such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is sputter deposited onto the flexible substrate.

[0279] Clause 21: The sensor array cover of clause 1, wherein the sensor array cover is disposable or single-use.

[0280] Item 22: The sensor array cover of Item 1, wherein the flexible substrate includes electrical contact pads disposed on the flexible substrate, wherein the top of the cover exposes the electrical contact pads, wherein the active electrodes are electrically connected to the electrical contact pads via conductive traces, and wherein the reference electrodes are electrically connected to the electrical contact pads via additional conductive traces.

[0281] Article 23: The sensor array cover of Article 1, wherein the reference electrode is a pseudo-reference electrode.

[0282] Clause 24. The sensor array cover of clause 1, wherein the flexible substrate is coupled to the bottom surface of the cover top by at least one of a biocompatible adhesive and a fastener.

[0283] Article 25: A system for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs, the system comprising: a microplate comprising a plurality of wells, wherein the plurality of wells comprises a test well and at least one control well, wherein each well is configured to receive an aliquot of a sample comprising an infectious pathogen, wherein at least one test well comprises an anti-infective drug, and wherein the control well does not contain an anti-infective drug; a sensor array cover configured to cover the microplate, wherein the sensor array cover comprises: a plurality of sensor units extending from a bottom surface of the sensor array cover, wherein each sensor unit is configured to extend into the well of the microplate so that the sensor units are The invention relates to a method for preparing a microplate comprising: a microplate and a sensor array cover covering the microplate; a sensor unit at least partially immersed in an aliquot of the sample in the well, wherein each sensor unit includes: an active electrode and a reference electrode; and a reader configured to receive the microplate and a sensor array cover covering the microplate in a receiving groove of the reader, wherein the reader includes conductive contacts for contacting the active electrode and the reference electrode of the sensor unit, wherein the reader is configured to determine the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in solution properties of the aliquot of the sample in the test well containing the anti-infective drug and any changes in solution properties of the aliquot of the sample in the control well over a period of time.

[0284] Article 26. The system of Article 25, wherein the microplate comprises 24 to 96 wells, and wherein the sensor array cover comprises 24 to 96 sensor units.

[0285] Clause 27: A system according to clause 25, wherein the anti-infective drug in the test well is lyophilized or dried.

[0286] Clause 28: The system of clause 25, wherein the anti-infective drug within the test well is in aqueous form.

[0287] Article 29: A system according to Article 25, wherein any change in the property of the solution in the well is detected without adding any exogenous reporter molecules to the well.

[0288] Article 30: A system according to Article 25, wherein the sample comprises a body fluid or a bacterial culture derived from a body fluid.

[0289] Article 31. A system according to Article 25, wherein the sample is a positive blood culture.

[0290] Article 32. A system according to Article 25, wherein the infectious agent comprises bacteria.

[0291] Article 33: The system according to Article 32, wherein the anti-infective drug comprises a bacteriostatic anti-infective drug, a bactericidal anti-infective drug, or a combination thereof.

[0292] Article 34. The system of Article 25, wherein the infectious agent comprises a fungus.

[0293] Clause 35: The system of clause 34, wherein the anti-infective agent comprises an antifungal agent.

[0294] Article 36: A system according to Article 25, wherein the sensor array cover further includes: a cover top; and a flexible substrate connected to the bottom surface of the cover top, wherein each sensor unit is implemented as a substrate strip or substrate segment partially cut out from the remaining portion of the flexible substrate, wherein the substrate strip or substrate segment of the flexible substrate is curled or bent vertically downward relative to the surrounding portion of the flexible substrate, wherein the active electrode is arranged on the substrate strip or substrate segment curled or bent vertically downward, and wherein the reference electrode is arranged on the substrate strip or substrate segment curled or bent vertically downward.

[0295] Clause 37: The system of Clause 36, wherein the cover top comprises a post extending from a bottom surface of the cover top, wherein the post is configured to abut or press against the base strip or base segment so that the base strip or base segment maintains its curled or bent configuration.

[0296] Clause 38: The system of clause 36, wherein the flexible substrate is made in part of a flexible polymer material.

[0297] Article 39: A system according to Article 38, wherein the flexible polymer material is partially made of polyethylene terephthalate (PET).

[0298] Clause 40: The system of clause 38, wherein the flexible polymer material is a flexible printed circuit board (PCB) material.

[0299] Clause 41: The system of clause 36, wherein the flexible substrate is made in part from a conductive metal substrate.

[0300] Item 42: The system of Item 41, wherein the conductive metal substrate is a stainless steel foil.

[0301] Clause 43: The system of clause 36, wherein the cap top is made in part from at least one of polystyrene, polypropylene, and cyclic olefin copolymer.

[0302] Clause 44: A system as described in Clause 36, wherein the flexible substrate includes electrical contact pads disposed on the flexible substrate for connecting to conductive contacts of the reader, wherein the cover top exposes the electrical contact pads, wherein the active electrode is electrically connected to the electrical contact pads via a conductive trace, and wherein the reference electrode is electrically connected to the electrical contact pads via an additional conductive trace.

[0303] Article 45. The system of Article 25, wherein the solution property is oxidation reduction potential (ORP), and wherein the active electrode comprises a redox active material.

[0304] Article 46. The system of Article 45, wherein the redox active material is a precious metal.

[0305] Article 47: The system of Article 45, wherein the redox active material is a metal oxide.

[0306] Article 48. A system according to Article 25, wherein the reference electrode comprises a reference electrode substance.

[0307] Clause 49: A system as described in Clause 48, wherein the reference electrode material comprises at least one of silver / silver chloride (Ag / AgCl) and carbon.

[0308] Article 50: A system according to Article 49, wherein the reference electrode material is coated or covered by an ion exchange membrane.

[0309] Item 51. The system of item 50, wherein the ion exchange membrane is a sulfonated tetrafluoroethylene based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane.

[0310] Clause 52: A system according to Clause 25, wherein at least one of the active electrode and the reference electrode is a screen printed electrode (SPE).

[0311] Clause 53: A system according to Clause 25, wherein at least one of the active electrode and the reference electrode is a plating electrode.

[0312] Clause 54: The system of clause 25, wherein at least one of the active electrode and the reference electrode is a sputter deposited electrode.

[0313] Clause 55: The system of clause 25, wherein the sensor array cover is disposable or single-use.

[0314] Article 56: A method for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs, the method comprising: introducing an aliquot of a sample containing the infectious pathogen into a well of a microplate, wherein the well comprises a test well and at least one control well, wherein at least one test well comprises an anti-infective drug and wherein the control well does not contain the anti-infective drug; covering the microplate with a sensor array cover, wherein the sensor array cover comprises a plurality of sensor units extending from a bottom surface of the sensor array cover, wherein each sensor unit is configured to extend into a well of the microplate so that the sensor unit is at least partially immersed in the aliquot of the sample in the well, wherein each sensor unit comprises an active electrode and a reference electrode; inserting the microplate covered by the sensor array cover into a reader, wherein the reader comprises conductive contacts for contacting the active electrodes and reference electrodes of the sensor units; determining the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in solution properties of the aliquot of the sample in the test well containing the anti-infective drug and any changes in solution properties of the aliquot of the sample in the control well over a period of time.

[0315] Item 57: The method of Item 56, further comprising diluting the sample with a diluent to a dilution ratio of about 1:1 to about 1:10,000 before introducing the sample into the well of the microplate.

[0316] Clause 58: The method of Clause 56, further comprising incubating the microplate covered by the sensor array cover within the reader at an incubation temperature of about 30°C to about 40°C.

[0317] Clause 59: The method of clause 56, wherein the microplate comprises 24 to 96 wells, and wherein the sensor array cover comprises 24 to 96 sensor units.

[0318] Article 60: The method according to Article 56, wherein the anti-infective drug in the test well is freeze-dried or dried.

[0319] Clause 61: The method of clause 56, wherein the anti-infective drug in the test well is in aqueous form.

[0320] Article 62: A method according to Article 56, wherein any change in the property of the solution in the well is detected without adding any exogenous reporter molecule to the well.

[0321] Article 63: A method according to Article 56, wherein the sample comprises a body fluid or a bacterial culture derived from a body fluid.

[0322] Article 64. The method of Article 56, wherein the sample is a positive blood culture.

[0323] Article 65. The method according to Article 56, wherein the infectious agent comprises bacteria.

[0324] Article 66: The method according to Article 65, wherein the anti-infective drug comprises a bacteriostatic anti-infective drug, a bactericidal anti-infective drug or a combination thereof.

[0325] Article 67. The method according to Article 56, wherein the infectious agent comprises a fungus.

[0326] Article 68. The method of Article 67, wherein the anti-infective agent comprises an antifungal agent.

[0327] Article 69: A method according to Article 56, wherein the sensor array cover further includes: a cover top; and a flexible substrate connected to the bottom surface of the cover top, wherein each sensor unit is implemented as a substrate strip or substrate segment partially cut out from the remaining portion of the flexible substrate, wherein the substrate strip or substrate segment of the flexible substrate is curled or bent vertically downward relative to the surrounding portion of the flexible substrate, wherein the active electrode is arranged on the substrate strip or substrate segment curled or bent vertically downward, and wherein the reference electrode is arranged on the substrate strip or substrate segment curled or bent vertically downward.

[0328] Clause 70: The method of clause 69, wherein the cover top comprises a post extending from a bottom surface of the cover top, wherein the post is configured to abut or press against the base strip or base segment so that the base strip or base segment maintains its curled or bent configuration.

[0329] Clause 71: A method according to clause 69, wherein the flexible substrate is made in part of a flexible polymer material.

[0330] Article 72: A method according to Article 71, wherein the flexible polymer material is partly made of polyethylene terephthalate (PET).

[0331] Article 73: A method according to Article 71, wherein the flexible polymer material is a flexible printed circuit board (PCB) material.

[0332] Clause 74: The method of clause 69, wherein the flexible substrate is made in part from a conductive metal substrate.

[0333] Clause 75: The method of clause 74, wherein the conductive metal substrate is a stainless steel foil.

[0334] Clause 76: The method of clause 69, wherein the cap top is partially made of at least one of polystyrene, polypropylene, and cyclic olefin copolymer.

[0335] Clause 77: A method according to clause 69, wherein the flexible substrate includes electrical contact pads disposed on the flexible substrate for connecting to conductive contacts of a reader, wherein the cover top exposes the electrical contact pads, wherein the active electrode is electrically connected to the electrical contact pads via a conductive trace, and wherein the reference electrode is electrically connected to the electrical contact pads via an additional conductive trace.

[0336] Clause 78: The method of clause 56, wherein the solution property is oxidation reduction potential (ORP), and wherein the active electrode comprises a redox active material.

[0337] Article 79. A method according to Article 78, wherein the redox-active substance is a noble metal.

[0338] Article 80: The method according to Article 78, wherein the redox active material is a metal oxide.

[0339] Clause 81: A method according to clause 56, wherein the reference electrode comprises a reference electrode substance.

[0340] Clause 82: The method of clause 81, wherein the reference electrode material comprises at least one of silver / silver chloride (Ag / AgCl) and carbon.

[0341] Article 83. A method according to article 82, wherein the reference electrode material is coated or covered by an ion exchange membrane.

[0342] Clause 84: The method according to clause 83, wherein the ion exchange membrane is a sulfonated tetrafluoroethylene based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane.

[0343] Clause 85: The method of clause 56, wherein at least one of the active electrode and the reference electrode is a screen printed electrode (SPE), such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is screen printed onto the sensor cell.

[0344] Clause 86: The method of clause 56, wherein at least one of the active electrode and the reference electrode is a plating electrode.

[0345] Clause 87: The method of clause 56, wherein at least one of the active electrode and the reference electrode is a sputter deposited electrode.

[0346] Clause 88: The method of clause 56, wherein the sensor array cover is disposable or single-use.

[0347] A plurality of embodiments have been described. However, it will be appreciated by those skilled in the art that various changes and modifications may be made to the present invention without departing from the spirit and scope of the embodiments. The elements of the systems, equipment, devices and methods shown in any embodiment are examples for specific embodiments and may be used in combination or otherwise for other embodiments within the present invention. For example, the steps of any method depicted in the accompanying drawings or described in the present invention do not need to achieve the desired result in the particular order or continuous order shown or described. In addition, other step operations may be provided, or steps or operations may be eliminated or omitted from the described methods or processes to achieve the desired result. In addition, any components or parts of any device or system described in the present invention or depicted in the accompanying drawings may be removed, eliminated or omitted to achieve the desired result. In addition, for the sake of brevity and clarity, some components or parts of the system, equipment or device shown or described herein have been omitted.

[0348] Accordingly, other embodiments are within the scope of the following claims and the description and / or drawings are regarded as illustrative rather than restrictive.

[0349] Each individual variation or embodiment described and illustrated herein has discrete components and features that can be readily separated or combined with the features of any other variation or embodiment. Modifications may be made to adapt a particular situation, material, composition of matter, process, process act or step to the objective, spirit or scope of the present invention.

[0350] The methods described herein may be performed in any order of events described that is logically feasible and in the order of events described. In addition, additional steps or operations may be provided or steps or operations may be eliminated to achieve the desired results.

[0351] In addition, when a numerical range is provided, each intermediate value between the upper and lower limits of the range and any other specified value or intermediate value within the specified range is included in the present invention. In addition, any optional features of the invention variants may be independently described and claimed, or may be described and claimed in combination with any one or more features described herein. For example, it should be considered that the description of a range from 1 to 5 has disclosed subranges such as from 1 to 3, from 1 to 4, from 2 to 4, from 2 to 5, from 3 to 5, etc., as well as individual numbers within the range (e.g., 1.5, 2.5, etc.) and any full or partial increments therebetween.

[0352] All prior subject matter (e.g., publications, patents, patent applications) mentioned herein are incorporated herein by reference in their entirety, except to the extent that such subject matter may conflict with the subject matter of the present invention (in which case the content herein shall prevail). The referenced items are provided solely for their disclosure prior to the filing date of the present application. Nothing herein shall be construed as an admission that the present invention is not entitled to antedate such material by virtue of prior invention.

[0353] Reference to a singular item includes the possibility of the presence of a plurality of the same item. More specifically, the singular forms "a," "an," "said," and "the" as used herein and in the appended claims include plural referents unless the context clearly dictates otherwise. It should also be noted that the claims can be drafted to exclude any optional elements. Therefore, this statement is intended to serve as an antecedent basis for the use of exclusive terms such as "only," "only," or the use of a "negative" limitation when reciting claim elements. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs.

[0354] When such phrases "at least one" modify multiple items or components (or an enumerated list of items or components), the phrase refers to any combination of one or more of those items or components. For example, the phrase "at least one of A, B, and C" refers to: (i) A; (ii) B; (iii) C; (iv) A, B, and C; (v) A and B; (vi) B and C; or (vii) A and C.

[0355] In understanding the scope of the present invention, the term "comprising" and its derivatives used herein are intended to be open terms, which specify the presence of the features, elements, components, groups, integers and / or steps, but do not exclude the presence of other unstated features, elements, components, groups, integers and / or steps. The foregoing also applies to words with similar meanings (such as the terms "including", "having" and their derivatives). In addition, the terms "part", "section", "portion", "member", "element" or "assembly" can have the dual meaning of a single part or multiple parts when used in the singular. As used herein, the following directional terms "forward, backward, above, downward, vertical, horizontal, below, transverse, lateral and vertical" and any other similar directional terms refer to the position of a device or equipment or the direction in which a device or equipment translates or moves.

[0356] Finally, the degree terms used herein, such as "substantially", "about" and "approximately", refer to a specified value or a specified value and a reasonable amount of deviation from the specified value (e.g., deviations of up to ±0.1%, ±1%, ±5% or ±10%, as such variations are appropriate) such that the end result is not significantly or substantially changed. For example, "about 1.0 cm" can be interpreted as "1.0 cm" or "between 0.9 cm and 1.1 cm". When a degree term (e.g., "about" or "approximately") is used to refer to a number or value in a portion of a range, the term can be used to modify both the minimum number or value and the maximum number or value.

[0357] The present invention is not intended to limit the scope of the specific form described, but is intended to cover the optional schemes, modifications and equivalent schemes of the variations or embodiments described herein. In addition, the scope of the present invention fully encompasses other variations or embodiments that may be obvious to those skilled in the art in view of the present invention.

Claims

1. A sensor array cover, comprising: Cover the top; a flexible substrate connected to the bottom surface of the cover top, wherein the flexible substrate includes a plurality of substrate strips or substrate segments partially cut out from a remaining portion of the flexible substrate, wherein at least one substrate strip or substrate segment of the flexible substrate is curled or bent vertically downward relative to a surrounding portion of the flexible substrate; An active electrode disposed on each vertically downwardly curled or bent substrate strip or substrate segment; as well as A reference electrode is disposed on each substrate strip or substrate segment that is curled or bent vertically downward.

2. The sensor array cover of claim 1, wherein the active electrode comprises a redox active material. The sensor array cover of claim 2 , wherein the redox active material is a noble metal. The sensor array cover of claim 2 , wherein the redox active material is a metal oxide. The sensor array cover of claim 1 , wherein the reference electrode comprises a reference electrode substance.

6. The sensor array cover of claim 5, wherein the reference electrode material comprises at least one of silver / silver chloride (Ag / AgCl) and carbon.

7. The sensor array cover of claim 6, wherein the reference electrode material is coated or covered by an ion exchange membrane.

8. The sensor array cover of claim 7, wherein the ion exchange membrane is a sulfonated tetrafluoroethylene-based fluoropolymer-copolymer or a polyaromatic polymer anion exchange membrane.

9. A sensor array cover according to claim 1, wherein the cover top includes a column extending from the bottom surface of the cover top, wherein the column is configured to abut or press against the base strip or base segment so that the base strip or base segment maintains its curled structure or bent structure.

10. A sensor array cover according to claim 9, wherein at least one of the substrate strips or substrate segments is abutted or pressed by at least one of the pillars so that a portion of the substrate strip or substrate segment is substantially perpendicular to the portion of the flexible substrate connected to the top of the cover.

11. The sensor array cover of claim 1, wherein the flexible substrate is made in part of a flexible polymer material.

12. The sensor array cover of claim 11, wherein the flexible polymer material is made in part from at least one of polyethylene terephthalate (PET) and a flexible printed circuit board (PCB) material.

13. The sensor array cover of claim 1, wherein the flexible substrate is made in part from a conductive metal substrate.

14. The sensor array cover of claim 1 , wherein at least one of the active electrode and the reference electrode is a screen printed electrode (SPE), such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is screen printed onto the flexible substrate.

15. The sensor array cover of claim 1, wherein at least one of the active electrode and the reference electrode is a plated electrode such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is plated onto the flexible substrate.

16. The sensor array cover of claim 1, wherein at least one of the active electrode and the reference electrode is a sputter deposited electrode such that at least one of the redox active material of the active electrode and the reference electrode material of the reference electrode is sputter deposited onto the flexible substrate.

17. The sensor array cover of claim 1, wherein the flexible substrate includes electrical contact pads disposed on the flexible substrate, wherein the cover top exposes the electrical contact pads, wherein the active electrodes are electrically connected to the electrical contact pads via conductive traces, and wherein the reference electrodes are electrically connected to the electrical contact pads via additional conductive traces.

18. The sensor array cover of claim 1, wherein the reference electrode is a pseudo reference electrode.

19. A system for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs, the system comprising: a microplate comprising a plurality of wells, wherein the plurality of wells comprises test wells and at least one control well, wherein each well is configured to receive an aliquot of a sample comprising the infectious pathogen, wherein at least one test well comprises an anti-infective drug, wherein the control well does not contain an anti-infective drug; A sensor array cover, the sensor array cover being configured to cover the microplate, wherein the sensor array cover comprises: A plurality of sensor units extending from a bottom surface of the sensor array cover, wherein each sensor unit is configured to extend into a well of the microplate such that the sensor unit is at least partially immersed in an aliquot of the sample within the well, wherein each sensor unit comprises: active electrode, and a reference electrode; and A reader configured to receive the microplate and a sensor array cover covering the microplate within a receiving well of the reader, wherein the reader includes conductive contacts for contacting active electrodes and reference electrodes of the sensor cells, wherein the reader is configured to determine the susceptibility of the infectious pathogen to the anti-infective drug based on any changes in solution characteristics of the sample aliquots within the test wells containing the anti-infective drug and any changes in solution characteristics of the sample aliquots within the control wells over a period of time.

20. A method for determining the susceptibility of an infectious pathogen to one or more anti-infective drugs, the method comprising: introducing an aliquot of the sample comprising the infectious pathogen into wells of a microplate, wherein the wells include a test well and at least one control well, wherein the at least one test well comprises an anti-infective drug, wherein the control well does not contain an anti-infective drug; covering the microplate with a sensor array cover, wherein the sensor array cover includes a plurality of sensor units extending from a bottom surface of the sensor array cover, wherein each sensor unit is configured to extend into a well of the microplate such that the sensor unit is at least partially immersed in an aliquot of the sample in the well, Wherein each sensor unit comprises an active electrode and a reference electrode; inserting the microwell plate covered by the sensor array cover into a reader, wherein the reader includes conductive contacts for contacting the active electrodes and reference electrodes of the sensor cells; and Susceptibility of the infectious pathogen to the anti-infective drug is determined based on any changes in solution characteristics of the sample aliquots in the test wells containing the anti-infective drug and any changes in solution characteristics of the sample aliquots in the control wells over a period of time.

Images