阅读说明：本技术 选择载玻片介质图像读取位置的方法和装置 (Method and apparatus for selecting slide medium image reading position ) 是由 丁忠 J·J-T·米勒 T·J·迪马尼奥 于 2019-06-27 设计创作，主要内容包括：本公开针对用于在反应池上定位目标位置并且使用目标位置实行测定的方法和装置。在示例实施例中,一种实行至少一种测定的方法包括：获得位于反应池上的流体样本的至少一个图像；以及基于至少一个图像来创建包括多个导数数据点的导数数据集合。该方法还包括：为多个导数数据点中的每一个确定图像梯度数据点,并且基于图像梯度数据点确定流体样本在反应池中的目标位置。该方法进一步包括：使用流体样本在反应池中的目标位置实行至少一种测定。(The present disclosure is directed to methods and apparatus for locating a target location on a reaction cell and performing an assay using the target location. In an example embodiment, a method of performing at least one assay comprises: obtaining at least one image of a fluid sample located on a reaction cell; and creating a derivative data set comprising a plurality of derivative data points based on the at least one image. The method further comprises the following steps: an image gradient data point is determined for each of the plurality of derivative data points, and a target location of the fluid sample in the reaction cell is determined based on the image gradient data points. The method further comprises the following steps: at least one assay is performed using the fluid sample at a target location in the reaction cell.)

1. A method of performing at least one assay, comprising:

obtaining, in a control unit, at least one image of a fluid sample located on a reaction cell;

creating, via the control unit, a derivative data set comprising a plurality of derivative data points based on the at least one image;

determining, via a control unit, an image gradient data point for each of a plurality of derivative data points;

determining, via the control unit, a target location of the fluid sample in the reaction cell based on the image gradient data points; and

at least one assay is performed using the fluid sample at a target location in the reaction cell via the control unit and associated assay system.

2. The method of claim 1, wherein the reaction cell comprises a solid medium, a dry slide, or a reaction cuvette.

3. The method of claim 1 or 2, wherein the target location comprises an approximate center of a homogeneous region of the fluid sample in the reaction cell.

4. A method as claimed in claim 1, 2 or 3 comprising using target locations from a plurality of images to carry out a plurality of assays.

5. The method of claim 1, 2, 3 or 4, wherein the derivative data points are based on a first derivative of a color in the at least one image.

6. The method of claim 1, 2, 3, 4, or 5, wherein determining a target location of a fluid sample comprises at least one of:

(i) using a first image gradient data point having a lower image gradient than a second image gradient data point; or

(ii) Second image gradient data points having a higher image gradient than the first image gradient data points are excluded.

7. The method according to claim 1 or 6, comprising removing image defects from at least one image via a control unit.

8. The method of claim 1 or 7, wherein at least one image is a two-dimensional image.

9. The method of claim 1 or 8, comprising forming, via the control unit, a read zone around the target location, and wherein performing at least one assay comprises using the read zone.

10. The method of claim 1, wherein determining a target location of a fluid sample comprises: an indicator reaction of an indicator molecule within a reaction cell formed by the combination of at least one reagent and the fluid sample is detected or measured.

11. A method of performing at least one assay, comprising:

obtaining, via a control unit, at least one image of a fluid sample located on a reaction cell;

creating, via the control unit, a derivative data set comprising a plurality of derivative data points based on the at least one image;

determining, via the control unit, a target location of the fluid sample based on the plurality of derivative data points;

forming a reading area around the target position via the control unit; and

at least one assay is performed using the read zone via the control unit and associated assay system.

12. The method of claim 11, wherein the reaction cell comprises a solid medium, a dry slide, or a reaction cuvette.

13. The method of claim 11 or 12, wherein the read area appears approximately circular in at least one image.

14. The method of claim 11, 12 or 13, wherein the read region appears approximately elliptical in at least one image.

15. The method of claim 11, 12, 13, or 14, comprising: via the control unit, an image gradient data point is determined for each of the plurality of derivative data points, and a target location of the fluid sample is determined based on the image gradient data points.

16. The method of claim 11 or 15, comprising: via the control unit and the associated measurement system, various measurements are carried out using the target positions from the plurality of images.

17. The method of claim 11 or 16, wherein at least one image is a two-dimensional image.

18. An apparatus for performing at least one assay, comprising:

a slide receiving location configured to receive at least one reaction cell having a fluid sample located thereon;

an imaging device positioned and arranged relative to the slide receiving location to obtain at least one image of the fluid sample located in the reaction cell; and

a control unit configured to: (i) determining a target location within a fluid sample located in a reaction cell by analyzing derivative data points derived from at least one image; and (ii) performing at least one determination based on the target location.

19. The apparatus of claim 18, wherein the reaction cell comprises a solid medium, a dry slide, or a reaction cuvette.

20. The apparatus of claim 19, wherein the solid medium comprises a second reaction cell.

21. The apparatus of claim 18 or 20, wherein the target location comprises an approximate center location of a homogeneous region of the fluid sample.

22. The apparatus of claim 18, 19, 20 or 21, wherein the control unit is configured to determine the target location by analyzing the image gradient data points for each of the plurality of derivative data points.

23. The apparatus of claim 22, wherein the control unit is configured to determine the target location by at least one of: (i) using a first image gradient data point having a lower image gradient than a second image gradient data point; or (ii) excluding second image gradient data points having a higher image gradient than the first image gradient data points.

24. The apparatus of claim 22, wherein the control unit is configured to determine the target position at an approximate geometric center of a first image gradient data point having a lower image gradient than a second image gradient data point.

25. The apparatus of claim 18 or 25, wherein the control unit is configured to perform a plurality of different determinations using the target position from the plurality of images.

26. The device of claim 18 or 25, wherein the target location of the fluid sample in the reaction cell corresponds to a location where a reaction of the indicator occurs, such that when the target molecule in the fluid sample reacts with the reagent in the reaction cell, the indicator is developed for display.

Technical Field

The present disclosure relates generally to methods and apparatus for locating a target location on a reaction cell, such as a dry slide or other porous/solid medium, so that the target location can be used to perform an assay, and more particularly to methods and apparatus for locating a read center of a fluid sample as a target location on a solid medium.

Background

One way to perform the assay is by using an image of the fluid sample that has been dispensed on a solid or porous medium. However, a problem with this approach is that the image profile may not be flat, with an axisymmetric gradient emanating from the center of the location where the fluid sample is dispensed. This problem can be caused, for example, by dispensing the sample at an undesirable location due to metering, media placement, or imprecision of the variable media. If the area for performing the measurement is taken at a predetermined position, there may be a large variation, which may reduce the accuracy of the performed measurement. Another problem is the presence of imperfections in the response image due to optical defects (e.g., dirt, coating defects, etc.) or unexpected flow patterns, which may degrade the assay signal.

Disclosure of Invention

The present disclosure relates to methods and apparatus for locating a target location in a reaction cell, such as a dry slide or other solid medium, and performing an assay using the target location, e.g., by obtaining an average optical intensity in a predefined area centered on the target location of the assay signal. In an example embodiment that may be used with any of the other embodiments disclosed herein, a method of conducting at least one assay includes obtaining at least one image of a fluid sample located on a reaction cell, creating a derivative data set including a plurality of derivative data points based on the at least one image, determining an image gradient data point for each of the plurality of derivative data points, determining a target location of the fluid sample in the reaction cell based on the image gradient data points, and conducting at least one assay using the target location of the fluid sample in the reaction cell.

In another embodiment that may be used with any of the other embodiments disclosed herein, the reaction cell is a solid medium, a dry slide, or a reaction cuvette.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the target location is an approximate center of a homogeneous region of the fluid sample in the reaction cell.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the method includes performing a plurality of assays using the target location from the plurality of images.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the derivative data points are based on a first derivative of a color in the at least one image. In an embodiment, the color in the at least one image represents the light intensity.

In another embodiment, which may be used with any other embodiment disclosed herein, determining the target location of the fluid sample comprises at least one of: (i) using a first image gradient data point having a lower image gradient than a second image gradient data point; or (ii) excluding second image gradient data points having a higher image gradient than the first image gradient data points. In an embodiment, this means taking (take) the first derivative across the whole image and then removing all pixels whose first derivative is above the threshold, so that the centers of the remaining pixels can be used to find the target position.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the method includes removing image defects from at least one image.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the at least one image is a two-dimensional image.

In another embodiment, which may be used with any of the other embodiments disclosed herein, determining a target location of a fluid sample comprises: an indicator reaction of an indicator molecule within a reaction cell formed by the combination of at least one reagent and the fluid sample is detected or measured.

In another embodiment that may be used with any of the other embodiments disclosed herein, the method comprises: forming a read zone around the target location, and wherein performing at least one assay comprises using the read zone.

In a general example embodiment that may be used with any other embodiment disclosed herein, a method of conducting at least one assay comprises: the method includes obtaining at least one image of a fluid sample located on a reaction cell, creating a derivative data set including a plurality of derivative data points based on the at least one image, determining a target location of the fluid sample based on the plurality of derivative data points, forming a read zone around the target location, and performing at least one assay using the read zone.

In another embodiment that may be used with any of the other embodiments disclosed herein, the reaction cell is a solid medium, a dry slide, or a reaction cuvette.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the read region appears approximately circular in at least one image.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the read region appears approximately elliptical in at least one image.

In another embodiment that may be used with any of the other embodiments disclosed herein, the method comprises: an image gradient data point is determined for each of the plurality of derivative data points, and a target location of the fluid sample is determined based on the image gradient data points.

In another embodiment that may be used with any of the other embodiments disclosed herein, the method comprises: a plurality of measurements are performed using the target location from the plurality of images.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the at least one image is a two-dimensional image.

In another general exemplary embodiment that can be used with any other embodiment disclosed herein, an apparatus for performing at least one assay comprises: a slide receiving location configured to receive at least one reaction cell having a fluid sample located thereon; an imaging device positioned and arranged relative to the slide receiving location to obtain at least one image of the fluid sample located in the reaction cell; and a control unit configured to: (i) determining a target location within a fluid sample located in a reaction cell by analyzing derivative data points derived from at least one image; and (ii) performing at least one determination based on the target location.

In another embodiment that may be used with any of the other embodiments disclosed herein, the reaction cell is a solid medium, a dry slide, or a reaction cuvette.

In another embodiment that may be used with any of the other embodiments disclosed herein, the solid medium comprises a second reaction cell.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the target location is an approximate center location of a homogeneous region of the fluid sample.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the control unit is configured to determine the target location by analyzing the image gradient data points for each of the plurality of derivative data points.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the control unit is configured to determine the target position by at least one of: (i) using a first image gradient data point having a lower image gradient than a second image gradient data point; or (ii) excluding second image gradient data points having a higher image gradient than the first image gradient data points. In an embodiment, this means taking the first derivative across the entire image and then removing all pixels whose first derivative is above the threshold, so that the centers of the remaining pixels can be used to find the target location.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the control unit is configured to determine the target position at an approximate geometric center of a first image gradient data point having a lower image gradient than a second image gradient data point.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the control unit is configured to perform a plurality of different determinations using the target location from the plurality of images.

In another embodiment, which may be used with any of the other embodiments disclosed herein, the target location of the fluid sample in the reaction cell corresponds to a location where a reaction of the indicator occurs, such that when the target molecule in the fluid sample reacts with the reagent in the reaction cell, the indicator is developed for display.

In another embodiment, which may be used with any of the other embodiments disclosed herein, any of the structures and functions disclosed in connection with fig. 1-37 may be combined with any of the other structures and functions disclosed in connection with fig. 1-37.

In view of the present disclosure and the above-described aspects, it is therefore an advantage of the present disclosure to provide an improved method and apparatus for locating a target location in a reaction cell for drying slides, reaction cuvettes or other solid media.

Advantages discussed herein may be found in one or some, and perhaps not all, embodiments disclosed herein. Additional features and advantages are described herein, and will be apparent from, the following detailed description and the figures.

Drawings

Embodiments of the present disclosure will now be explained in more detail, by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 illustrates a diagram of a side view of an example embodiment of a solid media according to the present invention;

FIG. 2 illustrates a diagram of an exploded perspective view of the solid media of FIG. 1;

FIG. 3 illustrates a diagram of an example embodiment of an assay device holding the solid medium of FIG. 1 according to the invention;

FIG. 4 illustrates a diagram of an example embodiment of a sample dispensing mechanism to dispense a fluid sample onto a solid medium according to the present disclosure;

FIG. 5 illustrates a diagram of an example embodiment of a liquid lens formed on a solid medium from a liquid sample as a result of the dispensing shown in FIG. 4;

FIG. 6 illustrates a diagram of an example embodiment showing a top perspective view and a bottom view of the example embodiment of the distribution illustrated in FIG. 5;

7A-7C illustrate diagrams of three example patterns that may be formed by a fluid sample on a solid medium;

FIG. 8 illustrates a diagram of an example embodiment of a method of performing at least one assay according to the present disclosure;

FIGS. 9A and 9B illustrate diagrams of an example embodiment of a method of detecting a target location in an image of a fluid sample on a solid medium according to the present disclosure;

FIG. 10 illustrates a diagram of different example patterns that may be formed on a solid medium by a fluid sample;

FIG. 11 illustrates an original image and a first spatial derivative that may be formed on a solid medium by a fluid sample;

FIG. 12 illustrates a diagram of different flaws that may be formed within an image of a fluid sample on a solid medium;

FIG. 13 illustrates a diagram of how dust spots on a solid media cause spikes in a corresponding image;

FIG. 14 illustrates a diagram of how a method according to the present disclosure improves assay accuracy;

FIG. 15 illustrates a diagram of how a method according to the present disclosure improves assay accuracy;

FIG. 16 illustrates a diagram of an embodiment of the solid media of FIGS. 1-5, according to an example embodiment of the present disclosure;

FIG. 17 illustrates a diagram of an image recorded by the assay system of FIG. 3 including a specimen placed on a stagnation area of each slide according to an example embodiment of the present disclosure;

fig. 18 and 20 illustrate images recorded by the assay system of fig. 3 in which dust or another contaminant is included in the sample, according to an example embodiment of the present disclosure.

FIGS. 19 and 21 illustrate diagrams showing analysis of a sample performed by an assay system based on the images of FIGS. 18 and 20; and

fig. 22-37 illustrate graphs of test result data comparing analytical performance of the example solid media of fig. 1-21 with known solid media, according to example embodiments of the present disclosure.

Detailed Description

The present disclosure relates to methods and apparatus for locating a target location on a reaction cell and performing an assay using the target location. As discussed in more detail below, the presently disclosed methods and apparatus are advantageous in, for example, improving computation time, reducing sensitivity to off-center photometry, avoiding edges/frames to minimize the effects of non-assay signals, and detecting and removing image defects (e.g., dirt, coating defects, wicking, etc.) to reduce bias or outliers. Image defects may also include foreign matter, bubbles, scratches, and the like. The present disclosure describes the reaction cell as a dry slide, a reaction cuvette, or a solid medium, but one of ordinary skill in the art will appreciate that the present disclosure can be used with other types of reaction cells, for example, porous media (such as nitrocellulose), semi-porous and solid media (such as Ouchterlony plates), liquid reagent devices (such as cuvettes), flow cells or reaction tubes, and/or solid media chips with embedded lateral flow arrays having optical measurement regions.

Fig. 1 and 2 illustrate example embodiments of reaction cells that may be used in accordance with the present disclosure. In fig. 1 and 2, a reaction cell is a solid medium 10 that may be used with an assay system 20 according to the present disclosure. For example, the solid medium 10 may be a single or multi-layer thin film element upon which the fluid sample may be dispensed. In the illustrated embodiment, the solid medium 10 includes a plurality of layers, including a first layer 12, which may be an upper slide mount layer configured to provide a hole therethrough to the top base layer for receiving the fluid sample. The first layer may also be configured to spread a fluid sample thereon. The solid medium 10 further comprises a second layer 14, which second layer 14 may be a reagent layer comprising reagents configured to react with the fluid sample to perform a specific assay. The second layer 14 may also include a support layer to provide support or rigidity to the reagent layer. The solid medium further comprises a third layer 16, which third layer 16 may be a filter layer providing a low wavelength cut-off filter to be used for optical analysis. The third layer 16 may include a lower slide mounting layer configured to provide a hole therethrough to the bottom base layer for optical analysis.

FIG. 3 illustrates an example embodiment of an assay system 20, the assay system 20 configured to locate a target location in an image of a fluid sample on a solid medium 10, and to use the target location to perform one or more assays. As illustrated, the assay system 20 may include: a slide receiving location 22 configured to receive at least one solid medium 10; a sample dispensing mechanism 32 configured to dispense a sample fluid onto the solid medium 10; an imaging device 24 positioned and arranged relative to the solid medium receiving location 22 to obtain at least one image of a fluid sample located on the solid medium 10; a light source 26 (e.g., one or more light emitting diode lamps) configured to project light onto the solid medium 10 such that the light can be modulated by a liquid sample dispensed onto the solid medium 10; and an optional optical filter 28 configured to modulate light from the light source 26 to a specific wavelength specific to the assay being performed.

In the illustrated embodiment, the slide receiving position 22 is configured to receive and hold the solid medium 10 while a fluid sample is added to the solid medium 10 and/or while the solid medium 10 is illuminated by the light source 26 and imaged by the imaging device 24. In the illustrated embodiment, the slide receiving position 22 includes: at least one bracket creating a first opening 22a and a second opening 22 b. The fluid sample may be added to the solid medium 10 at the first opening 22a of the slide receiving location 22 (e.g., through a hole in the first layer 12), while the second opening 22b of the slide receiving location 22 enables the solid medium 10 to be illuminated (e.g., through a hole in the third layer 16) and imaged after the fluid sample has reacted with the reagent. It should be further understood that the addition of the fluid sample may occur before the slide receiving position 22 receives the solid medium 10, and that the illumination and imaging of the solid medium 10 may occur at a first opening 22a at the top of the slide receiving position 22, opposite a second opening 22b at the bottom of the slide receiving position 22.

The assay system 20 of fig. 2 may further comprise: a control unit 30 configured to control one or more elements of the assay system 20, determine a target location of a fluid sample on the solid medium 10, and analyze the fluid sample on the solid medium 10 according to the method(s) described herein. The control unit 30 may include a processor and a non-transitory memory storing instructions for carrying out the methods described herein, wherein the processor executes the instructions to control one or more elements of the assay system 20 to carry out one or more assays.

Fig. 4 illustrates a fluid sample dispensed on a solid medium 10 by a sample dispensing mechanism 32 according to an example embodiment of the present disclosure. In an embodiment, the fluid sample may be dispensed on the solid medium 10 by a sample dispensing mechanism 32 manually controlled by a user before the solid medium 10 is inserted into the slide receiving position 22 of the assay system 20. The sample dispensing mechanism 32 may be, for example, a pipette or other fluid dispensing mechanism known in the art. Alternatively, the assay system 20 may include a sample dispensing mechanism 32, as illustrated in fig. 3. Here, the sample dispensing mechanism 32 may be controlled by a user or the control unit 30 to dispense the fluid sample onto (or into) the solid medium 10 before or after inserting the solid medium 10 into the slide receiving position 22 of the assay system 20.

FIG. 4 illustrates the sample dispensing mechanism 32 at time t₁To t₅To dispense the fluid sample onto the solid medium 10. During this time, stagnation and lateral flow may create a spatial gradient due to the concentration of coating material in the solid medium 10. As illustrated, at time t₁The fluid sample is ejected from the sample dispensing mechanism 32 onto the solid medium 10 and makes initial contact with the solid medium 10. At time t₂The fluid sample continues to be ejected from the sample dispensing mechanism 32 onto the solid medium 10, which may begin to form a stagnation area 44. At time t₃The fluid sample continues to be ejected from the sample dispensing mechanism 32 onto the solid medium 10 and spreads over the solid medium 10, which increases the size of the stagnation area 44. At time t₄The sample dispensing mechanism 32 begins to stop the ejection of the fluid sample, which causes fluid necking between the sample dispensing mechanism 32 and the solid medium 10, thereby forcing the stagnation area 44 directly below the sample dispensing mechanism 32. At time t₅The sample dispensing mechanism 32 no longer ejects the fluid sample, leaving a stagnation area 44. In the illustrated embodiment, the stagnation area 44 corresponds to an area with minimal variation. In some embodiments, the stagnation area 44 has relatively low optical density variability and/or the presence of relatively large indicators (e.g., sample dyes).

Fig. 5 illustrates a liquid lens 46 formed on the solid medium 10 by the fluid sample due to the stagnation area 44 created by the dispensing process of fig. 4. As illustrated, the fluid sample forms a circular liquid lens 46 over the solid medium 10. As shown in fig. 5, the circular liquid lens 46 is formed due to an axisymmetric fluid flow from the sample dispensing mechanism 32, which results in an axisymmetric distribution onto the coating material of the solid medium 10.

Fig. 6 illustrates a top perspective view and a bottom view showing an example embodiment of the distribution of liquid lens 46 over stagnation area 44. The subscripted plot of fig. 6 shows the light intensity in two dimensions (i.e., x and y space) across all pixels in the image. The center of the liquid lens 46 has a lower light intensity, while the edge of the liquid lens 46 has a higher light intensity. Graph 70 of fig. 6 has the same information as graph 72, but is presented in 3-dimensional form, with the z-axis representing light intensity, and with the x-axis and y-axis representing pixel location. If a pixel has a higher light intensity (at the x and y coordinates), it has a larger z value in the graphs 70 and 72. The light intensity is measured by a value called the "AD count" ("ADC"). Brighter pixels have a larger AD count than darker pixels.

Due to the differences in the measurement kinetics and the homogeneity of the coating material of the solid medium 10, there are different patterns that can be formed in the image taken of the fluid sample on the solid medium 10. Fig. 7A-7C illustrate three example patterns that may be formed. Fig. 7A shows a concave pattern, fig. 7B shows a convex pattern, and fig. 7C shows a complex pattern. Common features shared by all three patterns of fig. 7A-7C are: the stagnation region 44 at the center and the Z-axis symmetric radiation are disturbed by local inhomogeneities. The present disclosure uses this common feature to locate the center of a homogeneous region of a fluid sample (e.g., a relatively uniform light intensity) on a solid medium as a target location for use in conducting one or more assays.

Fig. 8 illustrates a method 100 for performing at least one assay by capturing an image and processing the image as disclosed herein. In an embodiment, the control unit 30 may include a processor and a non-transitory memory storing instructions to carry out the steps of the method 100. The processor executes instructions to cause the elements of the assay system 20 to carry out the steps of fig. 8. It will be appreciated by those of ordinary skill in the art that one or more of the steps shown in fig. 8 can be omitted, and/or additional steps can be added, and/or the order of certain steps can be rearranged, without departing from the spirit and scope of the present disclosure.

At step 102, imaging device 24 records at least one image of the fluid sample dispensed onto solid medium 10. For example, an image may be recorded while the light source 26 projects light onto the solid medium 10. The light from the light source 26 is configured such that the emitted light is transmitted by target molecules in the sample that have reacted with one or more reagents on the solid medium 10, thereby providing a visual indication of the reaction (e.g., indicator reaction). In some examples, the optical filter 28 and/or the filter provided by the solid media 10 is configured to modulate light from the light source 28. The imaging device 24 may be, for example, a charge coupled device ("CCD") camera, which may, for example, record a two-dimensional image showing an approximately elliptical or circular fluid sample on the solid medium 10. In an embodiment, the wavelengths required for a particular assay may be programmed into control unit 30 or provided to control unit 30, and then control unit 30 may control light source 26 and optical filter 28 such that the correct wavelengths of light for the assay being performed are projected onto solid medium 10 while the image is recorded by imaging device 24.

In step 104, the control unit 30 normalizes the image and determines the measured target position. Step 104 is shown and described in greater detail in fig. 9 and the corresponding description below. As explained in more detail below, step 104 may include one or more of the following: the method includes creating a derivative data set including a plurality of derivative data points based on the image, determining an image gradient data point for each of the plurality of derivative data points, determining a target location of the fluid sample on the solid medium based on the image gradient data point, and removing an image defect from the image.

At step 106, the control unit 30 uses the target position determined at step 104 by detecting, for example, light intensity or other values at the target position and/or at a specified area around the target position. In an embodiment, the target location may be used as a center point to form a specified area around the target location. For example, the target location may be used to create a read zone for detecting signals from light projected onto the solid medium 10. U.S. provisional application No. 62/693,120 entitled "Dry Slide use Reduced Reading Window" filed on 7/2 2018 further describes a method for creating a read zone around a target location and is incorporated herein by reference and relied upon. In other embodiments, the target location may be used, for example, to align the instrumentation system and/or optics, predict maintenance intervals, and/or minimize spectral errors due to reaction cell interference.

In step 108, the control unit 30 calculates an average light intensity of the image signal, for example from the light projected onto the solid medium 10 within the target position and/or a read zone created from the target position. In an embodiment, the average light intensity is the sum of the AD count values within the read region, divided by the total area of the read region (total number of pixels).

In step 110, the control unit 30 calculates a response using the target position. For endpoint determination (e.g., UREA), the response can be calculated by the difference in signal between two different readings of the same slide or solid medium 10. For rate determination (e.g., AST), the response may be calculated by the rate of change of signal over time from multiple readings of the same single slide or solid medium 10. Since the orientation of the slide or solid medium 10 may vary slightly over time due to rotation of the incubator, it is desirable to find the target location of each image on the same slide medium 10 over time.

At step 112, the control unit 30 completes the performance of the assay by calculating the concentration of the fluid sample, for example, using a calibration curve relating to the response to the concentration. A calibration curve may be obtained during a calibration process using a fluid having a known concentration and a response corresponding to the obtained concentration. In the calibration curve, the concentration is a known response function. In an embodiment, the control unit 30 may perform a variety of different determinations using target locations from a plurality of images.

Fig. 9A and 9B show a method 200 illustrating step 104 of method 100 in more detail. Specifically, fig. 9A and 9B illustrate an algorithm specifically designed to detect a target position (fig. 9A) and process an image defect (e.g., fix the image defect or report an error) (fig. 9B), which improves the measurement accuracy and reduces measurement deviation and outliers. As explained in more detail below, in detecting the target location (fig. 9A), the first derivative of the image at a particular step size is used to obtain the image gradient. A threshold is then applied to remove regions of high gradient. Finally, the centers of the remaining pixels in the image are used as the target position.

After finding the target location (e.g., the center of the homogeneous region with the smallest variation and the highest signal), the image quality can be checked by checking the distance between the target location and the sync location, detecting the number of spikes related to the target location, and analyzing the axial symmetry and noise level of the target location (fig. 9B). If one or more of the quantities or checks exceeds a certain threshold of the assay, an error code may be issued for the image indicating that the method 100 should be restarted with a new fluid sample, as the fluid sample being analyzed may be deemed unreliable. If no errors are found, the average light intensity of the image at the target location may be calculated as discussed above. In some embodiments, if the number of spikes is below a threshold, the method 200 is configured to remove spikes from the image, thereby improving the repeatability of the assay system. However, if the number of spikes is greater than the threshold, the image may be discarded or may be associated with an error code and/or alarm.

It will be appreciated by those of ordinary skill in the art that one or more of the steps shown in fig. 9A and 9B may be omitted, and/or additional steps may be added, and/or the order of certain steps may be rearranged, without departing from the spirit and scope of the present disclosure. As with the method 100, it should be understood that the control unit 30 may include a processor and non-transitory memory storing instructions to carry out the steps of the method of fig. 9A-9B. The processor executes instructions to cause the elements of the assay system 20 to carry out the disclosed steps.

Step 200 begins with the image recorded by imaging device 22 at step 102 of fig. 8. In step 200, the control unit 30 analyzes the image by associating the image with metadata, e.g. related to the assay type, the default center 40 of the fluid sample, the type of pattern detected for the fluid sample (e.g. concave, convex, complex), etc. The parameters stored in the metadata may be pre-programmed and stored in a memory of the control unit 30, or may be input by a user for a particular assay. The default center 40 of the fluid sample may be, for example, the center of the solid medium 10 or the center of the dispense location where the center of the fluid sample is expected to be located.

Depending on, for example, sensitivity to redistribution of soluble material in the solid medium 10, concentration of analyte/reagent, and/or chemical kinetics, the type of pattern detected for the fluid sample may be flat or non-flat (e.g., concave, convex, or more complex shapes). Fig. 10 illustrates different example patterns formed by a fluid dispensed on a solid medium 10, while fig. 11 illustrates views showing the original images and first spatial derivatives for different assays. Fig. 10 and 11 show that there is a small value at the stagnation area 44. As illustrated, the fluid sample may have, for example, a stagnation region 44 with a very small gradient (e.g., peak or trough intensity), a wash-out region with a larger gradient, and/or an edge with a large gradient (from a wet-dry interface or slide frame). U.S. provisional application No. 62/693,120 entitled "Dry Slide use Reduced Reading Window" filed on 7/2 in 2018 further describes how the wash-out region can affect the image and cause large gradients, the description of which is incorporated herein by reference and relied upon. According to the present method, when an appropriate threshold is applied, all large gradient regions may be removed and stagnation regions 44 may be identified.

In step 202, the control unit 30 normalizes the image by converting the image into a flat-field image if the image is not in such a form. In an embodiment, normalizing the image comprises: the optical energy applied across the read zone is normalized to reduce errors. In an embodiment, the normalization has two steps. The first step involves subtracting the dark read signal from the original signal. The dark read signal is a digital signal from the CCD sensor with the light source turned off. This calculation minimizes the background digital noise. The second step is to normalize the dark correction signal using the flat field signal by multiplying the signal by a flat field function. The flat field function can be obtained by reading a standard surface, which is a uniform, flat, white and/or reflective surface. The flat field function may be a function that generates a value of "1" for a standard surface over the entire surface. Assuming that the measured light intensity distribution isf=f(x, y) then the flat field isF=1/f。

In step 204, control unit 30 determines or accepts measurement-specific parameters, such as image cropping size, step size, threshold parameters, and the like. Assay specific parameters may be pre-programmed and stored in a memory of the control unit 30 or may be input by a user for a specific assay. The image cropping size may be, for example, the expected size of the image to be cropped at step 206, and may be input by the control unit 30 or automatically generated. In an example embodiment, the image crop size diameter may be approximately 4.5 mm around a center point (e.g., default center 40). The step size and threshold parameters are likewise input, or predetermined values are used in later steps of the process. Each measurement may have its own crop size, step size, and threshold (e.g., uricc crop size =3.64 mm, step size 0.28 mm, and threshold = 10).

In step 206, the control unit 30 cuts out the area 46 of the image. In an example, the control unit 30 crops out the areas 46 based on the expected location of the default center 40 of the fluid sample on the solid medium 10. In an embodiment, it is known from step 200 that the default center 40 is the center of the dispense location, e.g., the center of the solid medium 10 or the center where the fluid sample is desired. Accordingly, the image may be cropped, for example, to a circle (e.g., a circle having a diameter of 4.5 millimeters ("mm")) around the default center 40 based on the image cropping size determined at step 204. In another embodiment, the image may be cropped based on the detected light intensity, without limitation to any particular size. U.S. provisional application No. 62/693,120 entitled "Dry Slide use Reduced Reading Window" filed on 7/2 of 2018, the description of which is incorporated herein by reference and relied upon, further describes how to crop regions of an image to create read regions.

In step 208, the control unit 30 records the default center 40 of the cropped image. In an embodiment, the default center 40 is known from step 102, and the image is cropped based on the default center 40. In another embodiment, the default center 40 may not correspond to the center of the cropped image and may be determined based on the new cropped image. For example, the image may be cropped based on light intensity at step 206, and then the default center 40 may be recorded as the geometric center of the cropped image.

In steps 210 to 214, control unit 30 creates a derivative data set comprising a plurality of derivative data points based on the cropped image. In an embodiment, the derivative data points may be first derivative based on color in the image and may each include image gradient data points defining a binary image. In an embodiment, the color in the at least one image represents the light intensity. In an embodiment, the first derivative is the image light intensity in space. For example, each pixel in the image has a unique light intensity measured by the AD count (i.e., ADC). The first derivative may be the difference in light intensity between pixels at a predefined distance divided by the distance between pixels.

At step 210, control unit 30 creates a derivative data set by obtaining the absolute value of the first derivative (e.g., slope) of the cropped image at the determined particular step size determined at step 204. The first derivative can be calculated using the center difference method, with a certain step size being measured within the cropped image. For example, the derivative data set may be determined using the following formula:

Slope₁=max（|du/dx|，|du/dy|）。

here, u is the light intensity at one pixel in the image (AD count value). x and y are the coordinate locations of the pixel. The slope may be calculated in both x and y directions, and the maximum absolute value may be defined as the slope. The step size for calculating the derivative is measurement specific. As explained in more detail below, if Slope₁If the value is less than the threshold value, the value of the quality is 1, otherwise, the value of the quality is 0.

In steps 212 and 214, the control unit 30 determines an image gradient data point for each of a plurality of derivative data points in the derivative data set, thereby generating a binary image. In an embodiment, at step 212, if the Slope determined at step 210 is low₁Above the assay-specific threshold, the control unit 30 sets the image gradient data points to zero (0). That is, the higher gradient pixels are set to zero (0), and spikes, edges, etc. are removed from the binary image. Then, in step 214, if the image gradient data point is greater than a value of zero (0), the control unit 30 sets the image gradient data point to a value equal to one (1). I.e. if Slope₁Above the threshold, the image gradient data point at each pixel location (e.g., the quality at a location in the binary image) is zero (0), and if Slope is present₁Below the threshold, one (1). In an embodiment, a first image gradient data point having a lower image gradient than a second image gradient data point is included or set to one (1), and/or (ii) a second image gradient data point having a higher image gradient than the first image gradient data point is excluded or set to zero (0).

In step 216, the control unit 30 determines (e.g., elliptical or circular) a target location of the fluid sample based on the image gradient data points. For example, the target position may be calculated as a centroid of a binary image (e.g., the binary image shown in fig. 9A). In an embodiment, the center position may be obtained using the following formula:

in the formula, massm _ij Is its position indexiAndjas a function of (c). Coordinate valuesx _ij Andy _ij is also a position indexiAndjas a function of (c). The quality is equal to a value of "1" or a value of "0", depending on whether the quality is within a threshold across all indexes. Center of a shipX _c Coordinates are obtained by associating masses across all indexesxThe products between the coordinates are summed and thenThe sum product is calculated by dividing the total mass. Similarly, the centerY _c Coordinates are obtained by associating masses across all indexesyThe products between the coordinates are summed and then the sum product is divided by the total mass.

The centroid of the binary image may then be assigned as the target location of the fluid sample on the solid medium 10, which is the approximate geometric center of the homogeneous region of the fluid sample on the solid medium 10.

At steps 218-252 of fig. 9B, the control unit 30 is configured to detect and/or remove defects from the image (e.g., due to imperfections, dirt, coating defects, wicking, foreign matter, bubbles, scratches, etc. in the image) and/or determine an error condition based on the target location (i.e., the center of the fluid sample determined from step 216). The error may also indicate a problem with the reflectometer illumination system of the assay system 20, such as dirty projector optics. For example, as illustrated in fig. 12, there are many different imperfections in the image (e.g., dirt, eccentric distribution, wicking, foreign objects, bubbles, scratches, etc.) that can negatively impact the assay.

At step 218, the control unit 30 compares the target position determined at step 216 with the previously determined default center 40. In an embodiment, if the distance between the default center and the target location is greater than a threshold, the control unit 30 may report an error at step 220 and end the analysis at step 222. This may mean that the method 100 should then be restarted with a new fluid sample, since the fluid sample being analyzed is considered unreliable.

In step 224, the control unit 30 considers whether the flatness of the image is less than the threshold value. In an embodiment, the flatness of the image is the largest linear slope (absolute and normalized by the ADC mean) of the two linear slopes across the central vertical and horizontal lengths of the cropped image. Since the AD count value (ADC) varies over a large range (e.g., from 1,000 to 50,000) depending on the analyte concentration in the sample, the AD count value is normalized by dividing the AD count value by its average value. In this way, the slope change is more related to flatness than analyte concentration. An average of the AD counts is obtained, and then the AD count value is divided by the average. The slope may be positive or negative in that the absolute value of the slope is used to determine whether the image is flat. Although the light intensity distribution of the image may be concave or convex, its center (distribution position) is axisymmetric.

If the flatness of the image is less than the threshold at step 226, control unit 30 may report an error at step 228 and end the analysis at step 222. This may indicate that the method 100 should then be restarted with a new fluid sample, as the fluid sample being analyzed is considered unreliable.

In step 230, the control unit 30 creates a first derivative of the cropped image in the determined step size (e.g., step size one (1)). For example, the first derivative data may be determined using the following formula:

Slope₂=|du/dx|+|du/dy|。

in step 232, the control unit 30 obtains the Slope within the new center region₂MEAN (MEAN) and Standard Deviation (SD). In step 234, the control unit 30 determines whether the standard deviation/average is below a threshold. If the standard deviation/average is below the threshold, the control unit 30 may report an error at step 236 and end the analysis at step 238. This may mean that the method 100 should then be restarted with a new fluid sample, since the fluid sample being analyzed is considered unreliable.

In step 240, the control unit 30 may define two assay-specific constants:SpikeValueMaxandn. In an embodiment of the present invention,SpikeValueMaxrepresents a value determined by an experiment for measuring properties and is provided for each measurement, andnrepresenting positive numbers and used to calculate a defined spike detection thresholdSpikeGradientLimitThe value of (c). The control unit 30 may then be defined using, for example, the following formulaSpikeGradientLimit：

SpikeGradientLimit=min(SpikeValueMax，MEAN+n*SD)。

In the above-mentioned formula, the first and second,SpikeValueMaxand MEAN +nThe minimum of SD is used to define the thresholdSpikeGradientLimitThe threshold is used to detect whether the slope exceeds the limit in the image reading area.

In steps 242 and 244, control unit 30 removes large gradient spikes from the cropped image. In an example embodiment, the spike is by definitionSpikeMaskRemoved, wherein Slope of a point is removed₁Is greater thanSpikeGradientLimitThen, thenSpikeMaskEqual to a value of zero (0), if Slope of a point₁Is less thanSpikeGradientLimitThen, thenSpikeMaskEqual to a value of one (1). In another embodiment, spikes may be removed based on being above or below a predetermined threshold.

In step 246, the control unit 30 determines the total number of spikes detected in steps 240 and 242. If a small number of spikes are detected and removed from the image, the remaining pixels in the image can still be used to calculate the signal of the solid medium 10. However, if the number of spikes detected based on the measurement experiment exceeds the predefined limit, the control unit 30 may report an error in step 248 and end the analysis in step 252. This may mean that the method 100 should then be restarted with a new fluid sample, since the fluid sample being analyzed is considered unreliable.

In step 250, control unit 30 integrates within the cropped image defined by the target location, removing the detected defects so that the resulting image can be used in step 106 of method 100.

Fig. 13 illustrates an example of how a dust spot on the solid medium 10 may cause a spike in the corresponding image. As illustrated, by removing the spikes, any bias to measurements performed using the image can also be removed, making the measurements more reliable.

Fig. 14 and 15 illustrate the advantages achieved by the presently disclosed method. In fig. 14, TPxt means that the assay is TP ("total protein") in a multiplex test format (two tests per slide). COM (shown as a circle) represents the accuracy at the target location reading, which is found using the presently disclosed method. PS (shown as a square) represents the accuracy in reading at a pre-specified center (e.g., an assumed dispense location) without knowing the actual dispense location. The coefficient of variation (CV%) for each read diameter is the average of all test samples.

Fig. 16 illustrates an embodiment of the solid medium 10 of fig. 1-5, according to an example embodiment of the present disclosure. The solid medium 10 of fig. 16 includes: two chemical chips 1602a and 1602b corresponding to the stagnation region 44 described above. As discussed, the stagnation region corresponds to the region of the chemistry chip directly below the opening of the fluid metering tip. The stagnation area 44 may also be characterized by very little or no fluid flow in the radial direction. In the case of a radial outward positioning from the center of the spot and the area, there is a fluid flow vector pointing outward from the center of the chemical chip. A certain amount of the biochip reagent is washed out (wash out) in this area. The stagnant region or region 44 does not experience such washout once the chemical reaction is complete, and may have a different optical density than the region outside of stagnant region 44. In some examples, the stagnation zone or region 44 does not have a significant level of radial fluid flow, which results in a region of low optical variability and a region of high indicator (dye) presence.

In some examples, the chemistry chip and/or the stagnation area 44 corresponds to a target location of the fluid sample in the reaction cell. The target site or chemistry chip corresponds to the site where the indicator reaction takes place, such that when the target molecules in the fluid sample react with the reagents in the reaction cell, the indicator is developed for display. In some examples, the chemical chips 1602a and 1602b may each include a liquid-filled reaction cuvette. In these examples, imaging of the reaction cuvette may show bubbles, debris, and/or scratches on the cuvette walls. Identified defects can be identified and their impact mitigated relative to the analysis and determination results.

The use of the chemistry chip 1602 reduces the area required for the sample and allows more than one sample to be dispensed on the slide. Each chemical chip 1602 may receive the same fluid from a sample to enable the same or different analyses to be performed using the same solid medium 10. Alternatively, the chemical chips 1602 may each receive different fluids to enable the same or different analyses to be performed using the same slide 10. Additionally, although fig. 16 shows two chemical chips 1602, in other examples, the solid medium 10 may include additional chemical chips, such as three, four, etc. It will be appreciated that including more than one chemical chip on the solid medium 10 may improve the operating efficiency of the assay system 20, as multiple assays may be performed on the same solid medium 10 without moving the solid medium. In contrast, a solid medium having only a single chemical chip requires two or more separate solid media to be processed for the same analysis as a single solid medium 10 having a plurality of chemical chips.

Fig. 16 also shows an example of a chemical product solid media combination. The combination comprises: triglyceride cholesterol (TRI-CHOL), total bilirubin alkaline phosphatase (TBIL-ALKP), alanine aminotransferase-aspartate aminotransferase (ALTV-AST), UREA creatinine (UREA-CREA), calcium glucose (GLU-CA), and total albumin (ALB-TP). It should be appreciated that other combinations may be created and implemented on the solid medium 10.

Fig. 17 shows an image recorded by the assay system of fig. 3 including a sample placed on a chemical chip 1602 of a respective solid medium 10 according to an example embodiment of the present disclosure. As discussed above, the dispensing of the fluid sample creates a liquid lens 46 on the chemical chip 1602. The example solid media 10 of fig. 17 is configured to reduce sample size and improve the operating efficiency of the assay system 20 while maintaining analytical performance versus known conventional single slide testing. Since the sample volume placed in each chemical chip 1602 is small, the size of the area for analytical measurement is reduced. In some examples, the assay system 20 may use digital chemical techniques, as discussed above, to mitigate possible performance sensitivities. As shown in fig. 17, digital chemistry uses wavelength specific LEDs to record or capture an image of the solid media 10 on a digital image reflectometer. The assay system 20 uses one or more imaging algorithms to improve chemical results by ensuring that an optimal area of the sample is analyzed (as discussed above), even in the presence of changes in the orientation of the meter or including contaminants (e.g., dust).

As shown in fig. 17, the assay system 20 uses an imaging algorithm to determine the center 40, which is shown as centers 40 a-40 d of respective chips 1602 a-1602 d. As discussed above, the center 40 may or may not be the same as the default center, which is the theoretical center of a point if the dispensing tip and slide are perfectly aligned. The measurement system 20 then analyzes a certain radius around the center 40. The radius is between 1 mm and 8 mm, preferably about 2.25 mm, as shown by the dashed line in the figure.

FIG. 18 shows an image 1800 recorded by the assay system 20 of FIG. 3, wherein dust or another contaminant 1802 is included in the sample, according to an example embodiment of the present disclosure. Fig. 19 shows an analysis performed by assay system 20 on the sample of fig. 18 using the methods disclosed herein. The first graph 1902 shows the results of the analysis before the anomaly 1802 is detected and removed. The second graph 1904 shows the analysis results after the anomaly 1802 is detected and removed. In the illustrated example, the imaging algorithm detects anomalies and removes the anomalies from the processed image 1906 (derived from image 1800 of fig. 18). As a result, the anomaly is not included in the subsequent analysis of the sample. In some examples, the metering system 20 removes the anomaly by changing the pixel color associated with the anomaly to a color that is consistent with the surrounding pixel colors or a pixel color that indicates that there is no data for subsequent analysis.

Fig. 20 shows another image 2000 recorded by the assay system 20 of fig. 3, in which dust or another contaminant is included in the sample, according to an example embodiment of the present disclosure. Fig. 21 shows an analysis performed on a sample by the assay system 20. The first graph 2102 shows the analysis results before an anomaly is detected and removed. The second graph 2104 shows the analysis results after an anomaly is detected and removed. Similar to the previous example, the imaging algorithm detects the anomaly and removes the anomaly from the processed image 2106 (from image 2000 of fig. 20). As a result, the anomaly is not included in the subsequent analysis of the sample. Additionally, the assay system 20 is configured to move the center 40 of the image 2106 such that it reduces or minimizes a number of anomaly corrected locations included within the analysis field (e.g., a circle around the center).

Fig. 22-37 show test result data comparing the analytical performance of the example solid media 10 of fig. 1-21 with known slides or solid media. In the illustrated example of fig. 22 and 23, the assay system 20 is used to analyze the solid media 10 while a known slide or solid media is analyzed using a known conventional assay system. In an example, six of the example solid media 10 were evaluated for two serum concentrations using quality control materials on the example assay system 20. After the CLSI EP05 guidelines, the total laboratory performance accuracy (reported as percent of variance (% CV)) for a single calibration was evaluated with two replicates per run (run) over twenty days for a total of 80 replicates. The worst-case in-laboratory accuracy of the exemplary solid media 10 analyzed by the assay system 20 is compared to a corresponding single prior art test slide analyzed using a conventional assay system.

The% CV corresponds to the ratio of the standard deviation to the mean of the sample data, which provides an indication of the accuracy and repeatability in the assay, with lower values corresponding to higher accuracy and repeatability.

Fig. 22 illustrates a diagram of a table 2200 showing two serum levels for each slide chemistry (UREA, TRIG, GLU, ALB, TBIL, ALTV, CREA, CHOL, CA, TP, ALKP, and AST), and corresponding% CVs for a prior art slide using a conventional assay system and an example solid medium 10 using the example assay system 20. As illustrated, the solid media 10 using the assay system 20 had a lower% CV for nineteen of the twenty-four different tests. Fig. 23 shows a graph 2300 illustrating the% CV difference for each different slide chemistry test between a known prior art slide analyzed using the assay system 20 and the example solid media 10 disclosed herein. As shown, the use of the example solid medium 10 with the assay system 20 provides a better% CV for most slide chemistries compared to prior art slides.

In the illustrated examples of fig. 24 to 37, an external accuracy study was performed. In this study, prior art slides were analyzed using a conventional assay system. Test slides with twelve chemical components were analyzed for two serum concentrations. Statistical outliers were removed from the analysis. The remaining data were subjected to the Shapiro-Wilk normality test, in which the set indicating a severe deviation from normality was removed. The% CV of each slide serum-reagent batch (lot) combination was calculated. The% CV metric is averaged over the reagent batch and compared to the worst-case laboratory accuracy of the example solid media (10) analyzed by the example assay system 20.

Fig. 24 illustrates a diagram of a table 2400 showing two serum levels for each slide chemistry (UREA, TRIG, GLU, ALB, TBIL, ALTV, CREA, CHOL, CA, TP, ALKP, and AST), and corresponding% CVs for a prior art slide using a conventional assay system and an example solid medium 10 using the example assay system 20. As illustrated, the solid media 10 using the assay system 20 had a lower% CV for twenty of the twenty-four different tests. Fig. 25 shows a graph 2500 illustrating the% CV differences for each different slide chemistry test between a known prior art slide analyzed using the assay system 20 and the example solid media 10 disclosed herein.

Fig. 26-37 show graphs illustrating the results of each reagent lot number for an example solid media 10 and a known prior art slide. In the graph, the solid media 10 are provided with three batches, and are referred to as "XT … Lot #". Furthermore, the data relating to prior art slides are referred to as "ST … from field" and "ST mean". Each graph provides the% CV of accuracy for each serum (PVI) and (PVII).

Fig. 26 is a graph 2600 illustrating that an example solid medium 10 analyzed by the assay system 20 has a lower% CV of TRIG slide chemistry than a prior art slide analyzed by a conventional assay system. Fig. 27 is a graph 2700 illustrating that an exemplary solid medium 10 analyzed by the assay system 20 has a lower% CV of CHOL slide chemistry, with a slightly higher% CV than known prior art slides analyzed by conventional systems, except for the PVI serum of Lot 3. Fig. 28 is a graph 2800 showing that an exemplary solid medium 10 analyzed by the assay system 20 has a lower% CV of GLU slide chemistry than a prior art slide analyzed by a conventional assay system. Graph 2900 of fig. 29 shows that the example solid media 10 analyzed by the assay system 20 has a lower% CV of the CA slide chemistry than a prior art slide analyzed by a conventional assay system.

Additionally, the graph 3000 of fig. 30 shows that the example solid media 10 analyzed by the assay system 20 has a lower% CV of TP slide chemistry than prior art slides analyzed by conventional assay systems. The graph 3100 of fig. 31 shows that the example solid media 10 analyzed by the assay system 20 has a lower% CV of ALB slide chemistry compared to prior art slides analyzed by conventional assay systems. Graph 3200 of fig. 32 shows that an example solid medium 10 analyzed by assay system 20 has a lower% CV of ALTV slide chemical reagent than a prior art slide analyzed by a conventional assay system. Fig. 33 is a graph 3300 showing that an example solid medium 10 analyzed by the assay system 20 has a lower% CV of AST slide chemistry compared to prior art slides analyzed by conventional assay systems.

Figure 34 is a graph 3400 illustrating that an example solid medium 10 analyzed by the assay system 20 has a higher% CV of UREA slide chemistry than a prior art slide analyzed by a conventional assay system. However, the% CV difference between the example system and the conventional system was less than 0.5%. Figure 35 is a graph 3500 that illustrates that the example solid media 10 analyzed by the assay system 20 has a lower% CV of CREA slide chemistry as compared to prior art slides analyzed by conventional assay systems. Graph 3600 of fig. 36 shows that the example solid media 10 analyzed by the assay system 20 has a% CV of the ALKP slide chemical approximately equal to or lower than a prior art slide analyzed by a conventional assay system. Fig. 37 is a graph 3700 that shows that the example solid media 10 analyzed by the assay system 20 has a lower% CV of TBIL slide chemistry compared to prior art slides analyzed by conventional assay systems.

Conclusion

It should be understood that various changes and modifications to the presently preferred embodiments described herein will be apparent to those skilled in the art. Such changes and modifications can be made without departing from the spirit and scope of the present subject matter and without diminishing its intended advantages. It is therefore intended that such changes and modifications be covered by the appended claims.

Unless otherwise indicated, all numbers expressing quantities of ingredients, properties (such as molecular weight, reaction conditions, and so forth) used in the specification and claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the disclosure are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contains certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

The use of the terms "a" and "an" and "the" and similar referents in the context of this disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided herein, is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the disclosure.

The use of the term "or" in the claims means "and/or" unless explicitly indicated to refer only to alternatives or alternatives are mutually exclusive, although the present disclosure supports the definition of only alternatives and "and/or".

Groupings of alternative elements or embodiments of the present disclosure disclosed herein are not to be construed as limitations. Each group member may be referred to or claimed individually or in combination with other members of the group or other elements found herein. It is contemplated that one or more members of a group may be included in or deleted from the group for convenience and/or patentability reasons. When any such inclusion or deletion occurs, the specification is considered herein to encompass the modified group, and thus satisfies the written description of all Markush groups used in the appended claims.

Preferred embodiments of this disclosure are described herein, including the best mode known to the inventors for carrying out the disclosure. Of course, variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the disclosure to be practiced otherwise than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, this application is intended to cover any combination of the above-described elements in all possible variations thereof unless otherwise indicated herein or otherwise clearly contradicted by context.

Certain embodiments disclosed herein may be limited in the claims by way of language or language that consists essentially of language. When used in a claim, the transitional term "consisting of … …, whether filed as a amendment or added, does not include any element, step, or ingredient not specified in the claim. The transitional term "consisting essentially of limits the scope of the claims to the specified materials or steps as well as those materials or steps that do not materially affect the basic and novel characteristic(s). The embodiments of the present disclosure as so claimed are described and enabled herein either inherently or explicitly.

Additionally, it is to be understood that the embodiments of the disclosure disclosed herein are illustrative of the principles of the disclosure. Other modifications that may be employed are within the scope of the present application. Thus, by way of example, and not limitation, alternative configurations of the present disclosure may be utilized in accordance with the teachings herein. Accordingly, the disclosure is not limited to the exact details shown and described.