Method and system for judging positive and negative of ISFET sensor-based electronic microarray chip dot matrix

Abstract

The application discloses a kind of ISFET sensor-based electronic microarray chip dot matrix positive and negative judgment method and system, and relates to computer vision and image processing technical field.The method first obtains the position of chip dot matrix and primer stage and voltage data after extension reaction;Then, by setting low reaction threshold and noise threshold, bad hole is identified and eliminated;Then, the background value and effective signal value of each dot matrix are calculated, and finally the signal mean value of negative quality control, positive quality control and target area is obtained;Finally, by comparing the mean value of positive quality control with threshold to verify the effectiveness of experiment, and based on the comparison result of target mean value and threshold, the positive and negative of sample is automatically determined.The application realizes the automation of dot matrix detection result, quantitative interpretation, overcomes the defects that artificial interpretation is subjective, low in efficiency and easy to misjudge, and significantly improves the accuracy and robustness of detection.

Description

Technical Field

[0001] This invention belongs to the field of computer vision and image processing technology, and is particularly applicable to the interpretation of the properties of dot matrix experiments in scenarios such as image chips, microfluidics, and biological arrays. In particular, it relates to a method and system for determining the positive and negative properties of dot matrix in electronic microarray chips based on ISFET sensors. Background Technology

[0002] In the field of molecular diagnostics, dot-matrix-based multiplex PCR detection methods are often used to simultaneously detect multiple target genes, such as screening for multiple pathogens in infectious diseases and detecting multiple indicators of genetic diseases. After obtaining data within the dot-matrix region, it is necessary to rely on identifying the difference between the "dot-matrix signal" (such as fluorescence, color development, chemiluminescence, etc.) and the "control signal" to provide a reference interpretation conclusion and determine whether the target biomolecule is present in the sample. However, this method has the following drawbacks:

[0003] Traditional dot matrix detection and interpretation methods rely on visual observation or basic equipment, making them suitable for rapid initial screening without the need for specialized quantitative instruments. The core of these methods is to determine the presence or absence of a target molecule by the "presence or absence of a signal." They are suitable for colorimetric signals (such as brown / blue dots produced by HRP enzyme catalysis of substrates) and chemiluminescent signals (luminescent dots visible in a dark room), making them suitable for scenarios such as grassroots laboratories and on-site screening. However, they cannot quantify the content, and they are prone to misjudgment when the signal is weak (such as faint color development which may be ignored).

[0004] Therefore, there is an urgent need for a method that can quickly provide detection results and reduce manual interpretation of the dot matrix to meet the needs of practical applications. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method and system for qualitatively interpreting dot matrix results, so as to solve the problem of poor processing capability of existing methods for dot matrix datasets and improve detection efficiency and robustness.

[0006] To address the aforementioned technical problems, this invention provides a method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor, comprising the following steps:

[0007] Step S1: Obtain the dot matrix position: Identify the dot matrix region on the chip and mark the center coordinates and radius of each dot matrix circular region. The dot matrix region includes the negative quality control dot matrix region, the positive quality control dot matrix region, and the target measurement dot matrix region.

[0008] Step S2: Calculate the bad well distribution of the primer stage chip data D1 and the extended chip data D2, and mark the bad well locations.

[0009] Step S3: Calculate the background value of each dot matrix in each frame. For each dot matrix in each frame of data, calculate its background value based on its position information. The background value is based on the average value of all holes after excluding bad holes in the annular region surrounding the dot matrix.

[0010] Step S4: Mark the effective holes in the dot matrix according to the background value, and calculate the dot matrix signal for each frame.

[0011] Step S5: Determine the measurement signal of the dot matrix according to the data acquisition type. The final signal of each dot matrix is ​​the measurement signal of the extended chip data D2 minus the measurement signal of the primer stage chip data D1. After removing outliers according to the divided dot matrix regions, calculate the mean of each region and subtract the mean of the negative control dot matrix region: the mean of the negative control dot matrix region is denoted as Neg, the mean of the positive control dot matrix region is denoted as Pos, and the mean of the target measurement dot matrix region is denoted as Sam.

[0012] Step S6: Result determination: First, determine whether the experimental measurement is valid based on the mean value Pos of the positive control zone. If valid, further determine the positive or negative result based on the mean value Sam of the target measurement zone and the ratio rate of the mean value Sam of the target measurement zone to the mean value Pos of the positive control zone.

[0013] Furthermore, in this invention, step S2 specifically includes the following steps:

[0014] Step S21: Determine the low reaction threshold: When an empirical threshold is specified, the low reaction threshold is the empirical threshold; when no empirical threshold is specified, sort all the orifice voltage data from smallest to largest, and take the value at the 1 / 100th position of the data volume as the low reaction threshold.

[0015] Step S22: Determine the noise threshold: Perform sliding window mean filtering on the data of each hole in the time direction, subtract the mean-filtered data from the original data of each hole in time, and record the frame data with the largest absolute value as the noise of that hole; thereby calculate the average value and standard deviation of the noise data of all holes, and define the value of the average value plus 3 times the standard deviation as the noise threshold.

[0016] Step S23: Mark any hole that meets the criteria below the low reaction threshold or above the noise threshold as a bad hole, and remove bad holes in all subsequent calculations.

[0017] Furthermore, in step S22 of this invention, a five-point mean filtering is employed. Specifically, the steps are as follows: assuming the data for a certain hole in the frame is (a, b, c, d, e, f), it is first mirrored and expanded at the left and right boundaries to (c, b, a, b, c, d, e, f, e, d). Then, taking the average of two data points within a certain distance as the center of each data point, the filtered value of that data is obtained. That is, for example, taking a as the center, the average of (c, b, a, b, c) within a five-point window is the filtered value of a; taking b as the center, the average of (b, a, b, c, d) within a five-point window is the filtered value of b, and so on for other data.

[0018] Furthermore, in step S3 of this invention, the annular region is centered on the center coordinates of the dot matrix, and its radius is... The radius of the inner ring is multiplied by a factor of 1, and the radius of the outer ring is the inner ring radius plus a preset outward expansion distance R.

[0019] Furthermore, in step S4 of this invention, within the circular dot matrix region, holes with a value higher than the background value are designated as valid holes, and the signal of the dot matrix... The calculation formula is:

[0020]

[0021] in, The voltage value of the effective aperture in each frame. is the background value of the i-th frame of the dot matrix, where i is the i-th frame of the dot matrix and n is the number of effective holes v in the dot matrix.

[0022] In a further step of this invention, in step S5, data acquisition includes constant voltage measurement and triangular wave voltage measurement; for constant voltage measurement, the mean method is used: the mean of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix; for triangular wave voltage measurement, the maximum method is used: the maximum value of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix.

[0023] Furthermore, in step S5 of this invention, the outlier calculation method adopts the interquartile range: the data is sorted from smallest to largest, and the interquartile range is calculated. The interquartile range is the difference between the data located at three-quarters and one-quarter of the data volume. Data outside the range of n times the interquartile range is recorded as outliers. n is a parameter value that is independently adjusted by the experimenter, and the value range of n is 1.5 ≤ n ≤ 2.5.

[0024] Furthermore, in step S5 of this invention, the outlier calculation method adopts the standard deviation method: calculate the mean and standard deviation of the data, and record the data that are outside the mean plus m times the standard deviation as outliers. m can be adjusted by the experimenter, and the value of m is usually set to 2 or 3.

[0025] Furthermore, in step S6 of this invention, the method for determining the validity of the experiment is as follows: when the mean value Pos of the positive control lattice area is greater than or equal to the set positive control threshold T... Pos At that time, the measurements in this experiment were valid;

[0026] If the experiment is deemed valid, the sample's positive or negative status is determined:

[0027] The condition for determining a sample as negative is: the mean value Sam of the target measurement grid area is less than the set target threshold T. Sam Furthermore, the ratio rate of the target measurement patch mean Sam to the positive control patch mean Pos is less than the set ratio threshold T. rate ;

[0028] The condition for determining a sample as positive is: the mean value Sam of the target measurement grid area is greater than or equal to the set target threshold T. Sam Alternatively, the ratio rate (Sam) of the target measurement patch area to the mean value (Pos) of the positive control patch area is greater than or equal to the set ratio threshold T. rate .

[0029] This invention also provides a positive / negative determination system for an electronic microarray chip based on an ISFET sensor, specifically comprising the following modules:

[0030] ISFET sensor: used to detect the voltage at the bottom of the micropores of an electronic microarray chip, and to obtain chip data D1 during the primer stage and chip data D2 after extension.

[0031] Dot matrix position acquisition module: Based on the prior model, obtain the center coordinates and radius of the dot matrix's central region.

[0032] Bad hole location marking module: Based on the low reaction threshold and the calculated noise threshold, it identifies and marks bad holes in the primer stage chip data D1 and the extended chip data D2.

[0033] Background value calculation module: used to calculate the background value of each dot matrix in each frame.

[0034] Signal Calculation Module: Used to calculate the dot matrix signal for each frame.

[0035] The final signal calculation module for the region is used to calculate the regional mean after removing outliers from the divided dot matrix regions, and to obtain the mean value of the negative quality control dot matrix region (Neg), the mean value of the positive quality control dot matrix region (Pos), and the mean value of the target measurement dot matrix region (Sam).

[0036] The result determination module includes a validity determination unit and a positive / negative determination unit. The validity determination unit is used to determine whether the current experimental measurement is valid, and the positive / negative determination unit is used to determine the positive or negative of the sample if the experiment is valid.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] This invention provides a method for determining the positive and negative positivity of dot matrix in an electronic microarray chip based on an ISFET sensor. For the experimentally calibrated target dot matrix region, it uses set rules to eliminate errors in the pore position signal caused by noise and background factors, ultimately providing a statistically reasonable result. This avoids subjective and tedious manual operations such as observing fluorescence reactions, quickly providing experimental measurement results. This invention combines dot matrix position extraction and other preprocessing with background removal and effective point filtering mechanisms, enabling rapid and accurate determination of dot matrix measurement results, improving detection efficiency and precision. Through background removal and outlier elimination, this invention can screen out effective dot matrices, reducing the impact of noise and false detections on the results. This invention has strong robustness, can adapt to different dot matrix data qualities and complex scenarios, and has broad application prospects. Attached Figure Description

[0039] The specific embodiments of the present invention will be further explained below with reference to the accompanying drawings.

[0040] Figure 1 This is a flowchart of the method for determining the positive and negative properties of an electronic microarray chip based on an ISFET sensor, according to the present invention.

[0041] Figure 2 This is a schematic diagram of the low reaction threshold in Example 1.

[0042] Figure 3 This is a schematic diagram of the noise threshold in Example 1.

[0043] Figure 4 This is a schematic diagram of the dot matrix and background in Example 1.

[0044] Figure 5 This is a schematic diagram of the result determination in Example 1.

[0045] Figure 6 This is a system block diagram of the positive / negative determination system for an electronic microarray chip based on an ISFET sensor according to the present invention. Detailed Implementation

[0046] Example 1

[0047] The ISFET sensor-based electronic microarray chip dot matrix positive / negative determination method in this embodiment uses an ISFET sensor on the chip to detect the voltage at the bottom of the microwells. When specific nucleic acid probes are covalently bonded to the bottom of the microwells in a dot matrix form, these specific probes hybridize with the target sequence in the sample. After binding, they extend, and the charge at the bottom of the extended microwells changes, thus affecting the voltage change of the sensor. The voltage of these specific probes after binding with the target nucleic acid is different from the voltage of the microwells without binding nucleic acid molecules and the microwells in the negative region. Through algorithm analysis, it can be determined whether the target sequence has been bound, and thus determine the positive or negative of the sample.

[0048] In this embodiment, taking a 6-row, 6-column dot matrix distribution as an example, it is assumed that the first and second columns are negative control dot matrix regions, the third and fourth columns are positive control dot matrix regions, and the fifth and sixth columns are target measurement dot matrix regions; the primer stage chip data is called D1, and the extended chip data is called D2.

[0049] Combination Figure 1 The method for determining the positive and negative properties of an electronic microarray chip dot matrix based on an ISFET sensor in this embodiment specifically includes the following steps:

[0050] Step S1: Obtain the dot matrix position: Identify the dot matrix region on the chip and mark the center coordinates and radius of each dot matrix circular region. The dot matrix region includes the negative quality control dot matrix region, the positive quality control dot matrix region, and the target measurement dot matrix region.

[0051] In this embodiment, the dot matrix regions on the chip are identified by performing YOLO deep learning object detection or traditional edge detection on the chip data.

[0052] Step S2: Calculate the bad well distribution of the primer stage chip data D1 and the extended chip data D2, and mark the bad well locations.

[0053] In this embodiment, step S2 preferably includes the following steps:

[0054] Step S21: Determine the low response threshold: When an empirical threshold is specified, the low response threshold is the empirical threshold; when no empirical threshold is specified, sort all orifice voltage data from smallest to largest, and take the value at the 1 / 100th position of the data volume as the low response threshold, such as... Figure 2 As shown in the figure, the red line represents the low reaction threshold selected in this embodiment.

[0055] Step S22: Determine the noise threshold: Perform sliding window mean filtering on the data of each hole position in the time direction. Subtract the mean-filtered data from the original data of each hole in time, and record the frame with the largest absolute value as the noise of that hole. Then, calculate the average and standard deviation of the noise data for all holes, and define the average plus three times the standard deviation as the noise threshold. In this embodiment, specifically, N=3, that is, the noise threshold is the average of the noise data for all holes plus three times the standard deviation. Figure 3 As shown.

[0056] In this embodiment, preferably, step S22 uses five-point mean filtering. Specifically, the steps are as follows: Assuming the data for a certain hole in the frame is (a, b, c, d, e, f), first, mirror and expand it at the left and right boundaries to (c, b, a, b, c, d, e, f, e, d). Then, take the average of two data points within a certain distance centered on each data point to obtain the filtered value. That is: if centered on a, the average of (c, b, a, b, c) within a five-point window is the filtered value of a; if centered on b, the average of (b, a, b, c, d) within a five-point window is the filtered value of b, and so on for other data.

[0057] Step S23: Mark any hole that meets the criteria below the low reaction threshold or above the noise threshold as a bad hole, and remove bad holes in all subsequent calculations.

[0058] Step S3: Calculate the background value of each dot matrix in each frame. For each dot matrix in each frame of data, calculate its background value based on its position information. The background value is based on the average value of all holes within the annular region surrounding the dot matrix after excluding bad holes. Figure 4 As shown in the image, the area within the red circle is the dot matrix region, and the area between the two blue dotted lines is the background region.

[0059] In this embodiment, preferably, in step S3, the annular region is centered on the center coordinates of the dot matrix, and the radius of the dot matrix is... The radius of the inner ring is multiplied by a factor of 1, and the radius of the outer ring is the inner ring radius plus a preset outward expansion distance R. In this embodiment, the outward expansion distance R is usually related to the chip size and the number of dots, and is set by the experimenter when designing the chip. If no setting is made, half of the dot matrix radius can usually be used as the default, which can roughly ensure that the number of wells in the dot matrix is ​​equivalent to the number of wells in the ring.

[0060] Step S4: Mark the effective holes in the dot matrix according to the background value, and calculate the dot matrix signal for each frame.

[0061] In this embodiment, preferably, in step S4, within the circular dot matrix region, holes within the dot matrix that have a value higher than the background value are designated as valid holes, and the signal of the dot matrix... The calculation formula is:

[0062]

[0063] in, The voltage value of the effective aperture in each frame. is the background value of the i-th frame of the dot matrix, where i is the i-th frame of the dot matrix and n is the number of effective holes v in the dot matrix.

[0064] Step S5: Determine the measurement signal of the matrix based on the data acquisition type. The final signal of each matrix is ​​the measurement signal of the extended chip data D2 minus the measurement signal of the primer stage chip data D1. After removing outliers according to the divided matrix regions, calculate the mean of each region and subtract the mean of the negative control matrix region: Let the mean of the negative control matrix region be Neg, the mean of the positive control matrix region be Pos, and the mean of the target measurement matrix region be Sam. The three values ​​of Neg, Pos, and Sam are all the result of subtracting the mean of the negative control matrix region from the mean of the corresponding region, that is, Neg is numerically 0.

[0065] In this embodiment, preferably, in step S5, data acquisition includes constant voltage measurement and triangular wave voltage measurement; for constant voltage measurement, the mean method is used: the mean of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix; for triangular wave voltage measurement, the maximum method is used: the maximum value of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix.

[0066] In this embodiment, preferably, in step S5, the outlier calculation method adopts the interquartile range: sort the data from smallest to largest, calculate the interquartile range, where the interquartile range is the difference between the data located at three-quarters and one-quarter of the data volume, and denote data outside the range of n times the interquartile range as outliers, where n is a parameter value independently adjusted by the experimenter, and the value of n is in the range of 1.5 ≤ n ≤ 2.5. In this embodiment, the value of n is n = 1.5.

[0067] In this embodiment, preferably, in step S5, the outlier calculation method adopts the standard deviation method: calculate the mean and standard deviation of the data, and record the data that are outside the mean plus m times the standard deviation as outliers. m can be adjusted by the experimenter, and the value of m is usually set to 2 or 3. In this embodiment, the value of m is m=2.

[0068] Step S6: Result determination: First, determine whether the experimental measurement is valid based on the mean value Pos of the positive control zone. If valid, further determine the positive or negative result based on the mean value Sam of the target measurement zone and the ratio rate of the mean value Sam of the target measurement zone to the mean value Pos of the positive control zone.

[0069] In this embodiment, preferably, in step S6, the method for determining the validity of the experiment is: when the mean value Pos of the positive control lattice area is greater than or equal to the set positive control threshold T. Pos At that time, the measurements in this experiment were valid;

[0070] If the experiment is deemed valid, the sample's positive or negative status is determined:

[0071] The condition for determining a sample as negative is: the mean value Sam of the target measurement grid area is less than the set target threshold T. Sam Furthermore, the ratio rate of the target measurement patch mean Sam to the positive control patch mean Pos is less than the set ratio threshold T. rate ;

[0072] The condition for determining a sample as positive is: the mean value Sam of the target measurement grid area is greater than or equal to the set target threshold T. Sam Alternatively, the ratio rate (Sam) of the target measurement patch area to the mean value (Pos) of the positive control patch area is greater than or equal to the set ratio threshold T. rate .

[0073] In this embodiment, specifically, the positive quality control threshold T Pos Set to 50, target threshold T Sam Set to 100, ratio threshold T rate It is set at 97%.

[0074] The determination result of this embodiment is as follows: Figure 5 As shown, the light blue area represents the range of values ​​between the mean positive control value and the mean target value when the result is negative; if the result is positive, it should be above the light blue area; if it is to the left of the green line, the result is invalid.

[0075] Example 2

[0076] Combination Figure 6 The positive / negative determination system for the electronic microarray chip based on the ISFET sensor in this embodiment executes the determination method in Embodiment 1, specifically including the following modules:

[0077] ISFET sensor: used to detect the voltage at the bottom of the micropores of an electronic microarray chip, and to obtain chip data D1 during the primer stage and chip data D2 after extension.

[0078] Dot matrix position acquisition module: Based on the prior model, obtain the center coordinates and radius of the dot matrix's central region.

[0079] Bad hole location marking module: Based on the low reaction threshold and the calculated noise threshold, it identifies and marks bad holes in the primer stage chip data D1 and the extended chip data D2.

[0080] Background value calculation module: used to calculate the background value of each dot matrix in each frame.

[0081] Signal Calculation Module: Used to calculate the dot matrix signal for each frame.

[0082] The final signal calculation module for the region is used to calculate the regional mean after removing outliers from the divided dot matrix regions, and to obtain the mean value of the negative quality control dot matrix region (Neg), the mean value of the positive quality control dot matrix region (Pos), and the mean value of the target measurement dot matrix region (Sam).

[0083] The result determination module includes a validity determination unit and a positive / negative determination unit. The validity determination unit is used to determine whether the current experimental measurement is valid, and the positive / negative determination unit is used to determine the positive or negative of the sample if the experiment is valid.

[0084] Many specific details have been set forth in the foregoing description to provide a thorough understanding of the present invention. However, the above description is merely a preferred embodiment of the present invention, and the present invention can be implemented in many other ways different from those described herein. Therefore, the present invention is not limited to the specific embodiments disclosed above. Furthermore, any person skilled in the art can make many possible variations and modifications to the technical solutions of the present invention, or modify them into equivalent embodiments, using the methods and techniques disclosed above, without departing from the scope of the present invention. Any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention, without departing from the content of the present invention, shall still fall within the protection scope of the present invention.

Claims

1. A method for determining the positive or negative polarity of an electronic microarray chip based on an ISFET sensor, characterized in that: The steps include the following: Step S1: Obtain the dot matrix position: Identify the dot matrix area on the chip and mark the center coordinates and radius of each dot matrix circular area. The dot matrix area includes the negative quality control dot matrix area, the positive quality control dot matrix area and the target measurement dot matrix area. Step S2: Calculate the bad well distribution of the primer stage chip data D1 and the extended chip data D2, and mark the bad well locations; Step S3: Calculate the background value of each dot matrix in each frame. For each dot matrix in each frame of data, calculate its background value based on its position information. The background value is based on the average value of all holes after excluding bad holes in the annular area surrounding the dot matrix. Step S4: Mark the effective holes in the dot matrix according to the background value, and calculate the dot matrix signal for each frame; Step S5: Determine the measurement signal of the dot matrix according to the data acquisition type. The final signal of each dot matrix is ​​the measurement signal of the extended chip data D2 minus the measurement signal of the primer stage chip data D1. After removing outliers according to the divided dot matrix regions, calculate the mean of each region and subtract the mean of the negative control dot matrix region: the mean of the negative control dot matrix region is denoted as Neg, the mean of the positive control dot matrix region is denoted as Pos, and the mean of the target measurement dot matrix region is denoted as Sam. Step S6: Result determination: First, determine whether the experimental measurement is valid based on the mean value Pos of the positive control zone. If valid, further determine the positive or negative result based on the mean value Sam of the target measurement zone and the ratio rate of the mean value Sam of the target measurement zone to the mean value Pos of the positive control zone.

2. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: Step S2 specifically includes the following steps: Step S21: Determine the low reaction threshold: When an empirical threshold is specified, the low reaction threshold is the empirical threshold; when no empirical threshold is specified, sort all the orifice voltage data from smallest to largest, and take the value at the 1 / 100th position of the data volume as the low reaction threshold. Step S22: Determine the noise threshold: Perform sliding window mean filtering on the data of each hole in the time direction, subtract the mean-filtered data from the original data of each hole in time, and record the frame data with the largest absolute value as the noise of that hole; thereby calculate the average value and standard deviation of the noise data of all holes, and define the value of the average value plus 3 times the standard deviation as the noise threshold. Step S23: Mark any hole that meets the criteria below the low reaction threshold or above the noise threshold as a bad hole, and remove bad holes in all subsequent calculations.

3. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 2, characterized in that: In step S22, a five-point mean filter is used. The specific steps are as follows: Assuming that the data of a certain hole in the frame is (a, b, c, d, e, f), firstly, the data is mirrored and expanded to (c, b, a, b, c, d, e, f, e, d) at the left and right boundaries respectively. Then, the mean value of the data within two distances is calculated with each data as the center to obtain the filtered value of the data.

4. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S3, the annular region is centered on the center coordinates of the dot matrix, and its radius is... The radius of the inner ring is multiplied by a factor of 1, and the radius of the outer ring is the inner ring radius plus a preset outward expansion distance R.

5. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S4, within the circular dot matrix region, holes with a value higher than the background value are marked as valid holes, and the dot matrix signal... The calculation formula is: in, The voltage value of the effective aperture in each frame. is the background value of the i-th frame of the dot matrix, where i is the i-th frame of the dot matrix and n is the number of effective holes v in the dot matrix.

6. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S5, data acquisition includes constant voltage measurement and triangular wave voltage measurement. For constant voltage measurement, the mean method is used: the mean of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix. For triangular wave voltage measurement, the maximum method is used: the maximum value of each frame signal of each point matrix is ​​taken as the measurement signal of that point matrix.

7. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S5, the outlier calculation method adopts the interquartile range: sort the data from smallest to largest, calculate the interquartile range, where the interquartile range is the difference between the data located at three-quarters and one-quarter of the data volume, and record the data outside the range as outliers.

8. The method for determining the positive and negative properties of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S5, the outlier calculation method is the standard deviation method: calculate the mean and standard deviation of the data, and record the data that are outside the mean plus m times the standard deviation as outliers.

9. The method for determining the positive and negative polarity of an electronic microarray chip dot matrix based on an ISFET sensor according to claim 1, characterized in that: In step S6, the method for determining the validity of the experiment is as follows: when the mean value Pos of the positive control patch is greater than or equal to the set positive control threshold T. Pos At that time, the measurements in this experiment were valid; If the experiment is deemed valid, the sample's positive or negative status is determined: The condition for determining a sample as negative is: the mean value Sam of the target measurement grid area is less than the set target threshold T. Sam Furthermore, the ratio rate of the target measurement patch mean Sam to the positive control patch mean Pos is less than the set ratio threshold T. rate ; The condition for determining a sample as positive is: the mean value Sam of the target measurement grid area is greater than or equal to the set target threshold T. Sam Alternatively, the ratio rate (Sam) of the target measurement patch area to the mean value (Pos) of the positive control patch area is greater than or equal to the set ratio threshold T. rate .

10. A positive / negative determination system for an electronic microarray chip based on an ISFET sensor, characterized in that: include: ISFET sensor: used to detect the voltage at the bottom of the micropores of an electronic microarray chip, and to obtain chip data D1 during the primer stage and chip data D2 after extension; Dot matrix position acquisition module: Obtains the center coordinates and radius of the dot matrix's central region based on a prior model; Bad hole location marking module: Based on the low reaction threshold and the calculated noise threshold, it identifies and marks bad holes in the primer stage chip data D1 and the extended chip data D2. Background value calculation module: used to calculate the background value of each dot matrix in each frame; Signal calculation module: used to calculate the dot matrix signal for each frame; The final signal calculation module for the region is used to calculate the regional mean after removing outliers from the divided dot matrix regions, and to obtain the mean value of the negative quality control dot matrix region (Neg), the mean value of the positive quality control dot matrix region (Pos), and the mean value of the target measurement dot matrix region (Sam). The result determination module includes a validity determination unit and a positive / negative determination unit. The validity determination unit is used to determine whether the current experimental measurement is valid, and the positive / negative determination unit is used to determine the positive or negative of the sample if the experiment is valid.

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