Electronic microarray chip dot matrix negative and positive judgment method and system based on ISFET sensor
By using ISFET sensors to automatically process dot matrix data, noise and background interference are eliminated, enabling rapid and accurate determination of positive and negative dot matrix values. This solves the problem of weak signals and easy misjudgment in traditional methods, and improves detection efficiency and accuracy.
Patent Information
- Application Number
- CN202511484588.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-01-13
AI Technical Summary
Existing technologies cannot quantify the content in dot matrix detection, and are prone to misjudgment when the signal is weak. Traditional methods rely on manual interpretation and lack rapid and accurate quantitative analysis methods.
An electronic microarray chip dot matrix positive and negative determination method based on ISFET sensor is adopted. By identifying the dot matrix region, calculating the background value and noise threshold, eliminating outliers, and combining signal calculation and ratio determination, the result interpretation is automated.
It can quickly and accurately determine the results of dot matrix measurements, improve detection efficiency and accuracy, reduce manual intervention, has strong robustness, and can adapt to different data quality and complex scenarios.
Smart Images
Figure CN121329923A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application belongs to the technical field of computer vision and image processing, and is especially suitable for interpreting the properties of dot array in the scene of image chip, microfluidic, biological array, and especially relates to a dot array positive and negative judgment method and system based on ISFET sensor electronic microarray chip. BACKGROUND
[0002] In the field of molecular diagnosis, dot array-based multiplex PCR detection methods are often used in scenarios for simultaneously detecting multiple target genes, such as infectious disease multi-pathogen screening and genetic disease multi-index detection. After obtaining the data in the dot array area, it is necessary to rely on the difference between the "dot array signal" (such as fluorescence, color development, chemiluminescence, etc.) and the "control signal" to give a reference interpretation conclusion to determine whether the target biomolecule exists in the sample. However, such a method has the following defects:
[0003] The traditional dot array detection interpretation method is observed by naked eye or basic equipment, which is suitable for rapid preliminary screening and does not require professional quantitative instruments. The core is to determine whether the target molecule exists by "signal presence or absence", which is suitable for color development signals (such as brown / blue dots produced by HRP enzyme catalyzing substrate), chemiluminescence signals (luminescent dots visible in a dark room), and is suitable for basic laboratories and on-site screening scenarios, but cannot quantify the content and is prone to misjudgment when the signal is weak (such as light color development that may be ignored).
[0004] Therefore, there is an urgent need for a method that can quickly give detection results and reduce manual interpretation of dot arrays to meet the needs of practical applications. SUMMARY
[0005] The purpose of the present application is to overcome the shortcomings of the prior art and provide a method and system for qualitatively interpreting dot array results to solve the problem of poor dot array data set processing capability of existing methods and improve detection efficiency and robustness.
[0006] To solve the above technical problems, the present application provides a dot array positive and negative judgment method based on ISFET sensor electronic microarray chip, which comprises the following steps:
[0007] Step S1: Obtain the dot array position: identify the dot array area on the chip, and mark the center coordinates and radius of each dot array circular area, wherein the dot array area includes negative quality control dot array area, positive quality control dot array area and target measurement dot array area.
[0008] Step S2: Calculate the bad well distribution of primer stage chip data D1 and extended chip data D2, and mark the bad well position.
[0009] Step S3: Calculate the background value of each dot in each frame, for each dot in each frame, calculate its background value based on its position information, and the background value is based on the average value of all holes in the annular region around the dot after excluding bad holes.
[0010] Step S4: Label the valid holes in the dot according to the background value, and calculate the dot signal of each frame.
[0011] Step S5: Determine the measurement signal of the dot according to the data acquisition type, the final signal of each dot is the measurement signal of the extended chip data D2 minus the measurement signal of the primer stage chip data D1, and the average value of each region is calculated after excluding abnormal values in the divided dot region and subtracting the average value of the negative quality control dot region: the average value of the negative quality control dot region is Neg, the average value of the positive quality control dot region is Pos, and the average value of the target measurement dot region is Sam.
[0012] Step S6: Perform result determination: first, determine whether the current experiment measurement is valid according to the average value Pos of the positive quality control dot region, and if valid, further determine the positive and negative of the experimental result according to the average value Sam of the target measurement dot region and the ratio rate of the average value Sam of the target measurement dot region and the average value Pos of the positive quality control dot region.
[0013] Further in the present application, step S2 specifically comprises the following steps:
[0014] Step S21: Determine the low reaction threshold: when the empirical threshold is specified, the low reaction threshold is the empirical threshold; when the empirical threshold is not specified, sort all hole voltage data from small to large, and take the value at the first percentile position 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 the hole; thus, the average value and standard deviation of all noise data of the holes are calculated, and the value of the average value plus 3 times the standard deviation is set as the noise threshold.
[0016] Step S23: Mark any hole that meets the low reaction threshold or is higher than the noise threshold as a bad hole, and exclude the bad hole in all subsequent calculations.
[0017] Further in the application, in step S22, five-point mean filtering is adopted, and the specific steps are as follows: assuming that the data of a certain hole on a frame is (a, b, c, d, e, f), first, mirror extension is performed on the left and right boundaries to (c, b, a, b, c, d, e, f, e, d), and then the mean value of the data within a distance of two data from each data is taken to obtain the filtered value of the data. That is, if a is taken as the center, the mean value of (c, b, a, b, c) in the five-point window is the filtered value of a; if b is taken as the center, the mean value of (b, a, b, c, d) in the five-point window is the filtered value of b, and other data are taken in the same way.
[0018] Further in the application, in step S3, the annular region takes the center coordinate of the dot matrix as the center of a circle, takes the radius of the dot matrix as the inner circle radius, and takes the inner circle radius plus a preset expansion distance R as the outer circle radius.
[0019] Further in the application, in step S4, in the circular dot matrix region, the holes higher than the background value in the dot matrix are marked as effective holes, and the calculation formula of the signal of the dot matrix is as follows:
[0020]
[0021] Among them, v is the voltage value of each frame of effective holes, b i is the background value of the i th frame of the dot matrix, i is the i th frame of the dot matrix, n is the number of effective holes v in the dot matrix. Further in the application, in step S5, data acquisition includes constant voltage measurement and triangular wave voltage measurement; for constant voltage measurement, mean value method is adopted for processing: the mean value of each frame signal of each dot matrix is taken as the measurement signal of the dot matrix; for triangular wave voltage measurement, maximum method is adopted for processing: the maximum value of each frame signal of each dot matrix is taken as the measurement signal of the dot matrix.
[0022] Further in the application, in step S5, the calculation method of the abnormal value adopts the quartile method: the data is sorted from small to large, the interquartile range is calculated, the interquartile range is the difference between the data at three-quarters and one-quarter of the data amount, and the data outside n times the interquartile range is recorded as the abnormal value. n is a parameter value adjusted by the experiment personnel, and the value range of n is 1.5≤n≤2.5.
[0023] Further in the application, in step S5, the calculation method of the abnormal value adopts the standard deviation method: the mean value and the standard deviation of the data are calculated, and the data outside the mean value plus m times the standard deviation is recorded as the abnormal value. m can be adjusted by the experiment personnel, and m is usually taken as 2 or 3 for calibration.
[0024] Further in the application, in step S5, the calculation method of the abnormal value adopts the standard deviation method: the mean value and the standard deviation of the data are calculated, and the data outside the mean value plus m times the standard deviation is recorded as the abnormal value. m can be adjusted by the experiment personnel, and m is usually taken as 2 or 3 for calibration.
[0025] Further in the present application, the experimental effectiveness determination method in step S6 is: when the positive quality control dot array mean Pos is greater than or equal to the set positive quality control threshold T Pos , the present experiment is effective;
[0026] In the case of determining that the experiment is effective, the sample positive and negative determination is performed:
[0027] The condition for determining that the sample is negative is that the target measurement dot array mean Sam is less than the set target threshold T Sam , and the ratio rate of the target measurement dot array mean Sam to the positive quality control dot array mean Pos is less than the set ratio threshold T rate ;
[0028] The condition for determining that the sample is positive is that the target measurement dot array mean Sam is greater than or equal to the set target threshold T Sam , or the ratio rate of the target measurement dot array mean Sam to the positive quality control dot array mean Pos is greater than or equal to the set ratio threshold T rate .
[0029] The present application also provides an ISFET sensor-based electronic microarray chip dot array positive and negative determination system, which specifically comprises the following modules:
[0030] ISFET sensor: used for detecting the voltage at the bottom of the microhole of the electronic microarray chip, obtaining primer stage chip data D1 and post-extension chip data D2.
[0031] Dot array position acquisition module: based on a priori model, the center coordinates and radius of the dot array center region are obtained.
[0032] Bad hole position marking module: based on a low reaction threshold and a calculated noise threshold, the holes in the primer stage chip data D1 and the post-extension chip data D2 are judged and marked for bad holes.
[0033] Background value calculation module: used for calculating the background value of each dot array on each frame.
[0034] Signal calculation module: used for calculating the dot array signal of each frame.
[0035] Region final signal calculation module: used for calculating the region mean after removing abnormal values according to the divided dot array regions, obtaining the negative quality control dot array mean Neg, the positive quality control dot array mean Pos and the target measurement dot array mean Sam.
[0036] Result determination module: including an effectiveness determination unit and a positive and negative determination unit, the effectiveness determination unit is used for determining whether the present experiment is effective, and the positive and negative determination unit is used for determining the positive and negative of the sample in the case of determining that the experiment is effective.
[0037] Compared with the prior art, the present application has the following beneficial effects:
[0038] The ISFET sensor-based electronic microarray chip dot array positive and negative judgment method of the present application aims at the target dot array region calibrated by experiments, eliminates the well signal errors caused by noise and background and other factors by setting rules, and finally gives a relatively reasonable result judgment in a statistical sense, avoiding subjective and tedious operations such as observing fluorescence reaction, and quickly giving experimental determination results. The present application combines dot array position extraction and other pretreatments, adopts background elimination and effective point filtering mechanism, can quickly and accurately judge dot array determination results, and improves the detection efficiency and precision. The present application can screen out effective dot arrays by background removal and abnormal point elimination, and reduce the influence of noise and false detection on the results. The present application has strong robustness, can adapt to different dot array data quality and complex scenes, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS
[0039] The specific embodiments of the present application will be further illustrated below in combination with the drawings.
[0040] Figure 1 The flowchart of the ISFET sensor-based electronic microarray chip dot array positive and negative judgment method of the present application.
[0041] Figure 2 The low reaction threshold value in Example 1 is shown in the schematic diagram.
[0042] Figure 3 The noise threshold value in Example 1 is shown in the schematic diagram.
[0043] Figure 4 The dot array and background in Example 1 are shown in the schematic diagram.
[0044] Figure 5 The result judgment in Example 1 is shown in the schematic diagram.
[0045] Figure 6 The system block diagram of the ISFET sensor-based electronic microarray chip dot array positive and negative judgment system of the present application. DETAILED DESCRIPTION
[0046] Example 1
[0047] The ISFET sensor-based electronic microarray chip dot matrix positive and negative judgment method of the embodiment detects the voltage at the bottom of the microwell through the ISFET sensor on the chip. When specific nucleic acid probes are covalently connected to the bottom of the microwell in the form of a dot matrix, these specific probes hybridize with the target sequence in the sample, and after binding, extension occurs. The charge at the bottom of the microwell changes, thereby affecting the voltage change of the sensor. The voltage after the specific probe binds to the target nucleic acid is different from the voltage of the microwell and the microwell in the negative area without binding to the nucleic acid molecule. Through algorithm analysis, it can be judged whether the target sequence is combined, and then the positive and negative of the sample is judged.
[0048] In the embodiment, specifically, taking a 6-row 6-column dot matrix distribution as an example, the first and second columns are assumed to be negative quality control dot matrix areas, the third and fourth columns are positive quality control dot matrix areas, and the fifth and sixth columns are target measurement dot matrix areas. The primer stage chip data is referred to as D1, and the chip data after extension is referred to as D2.
[0049] In combination Figure 1 , the ISFET sensor-based electronic microarray chip dot matrix positive and negative judgment method of the embodiment specifically includes the following steps:
[0050] 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 negative quality control dot matrix areas, positive quality control dot matrix areas, and target measurement dot matrix areas.
[0051] In the embodiment, specifically, the dot matrix areas on the chip are identified through YOLO deep learning target detection or traditional edge detection methods on chip data.
[0052] Step S2: Calculate the bad well distribution of the primer stage chip data D1 and the chip data D2 after extension, and mark the bad well position.
[0053] In the embodiment, preferably, in step S2, the following steps are specifically included:
[0054] Step S21: Determine the low reaction threshold value: when the empirical threshold value is specified, the low reaction threshold value is the empirical threshold value; when the empirical threshold value is not specified, sort all well site voltage data from small to large, and take the value at the first percentile position as the low reaction threshold value, as shown in Figure 2 The red line position in the figure represents the low reaction threshold value selected in the embodiment.
[0055] Step S22: determining noise threshold: sliding window mean filtering the data of each well site in the time direction, subtracting the mean filtered data from the original data of each well in time, and recording the frame data with the maximum absolute value as the noise of the well. The average value and standard deviation of all well noise data are calculated to determine the noise threshold as the average value plus 3 times the standard deviation. In this embodiment, N=3, i.e. the noise threshold is the average value of all well noise data plus 3 times the standard deviation, as shown in FIG. 4. Figure 3
[0056] In this embodiment, preferably, five-point mean filtering is used in step S22, and the specific steps are as follows: assuming that the data of a well in a frame is (a, b, c, d, e, f), first mirror extending the data to (c, b, a, b, c, d, e, f, e, d) at the left and right boundaries, and then taking the mean value of the data within a distance of two data centers to obtain the filtered value of the data. That is, as the center of a, the mean value of (c, b, a, b, c) in the five-point window is the filtered value of a; as the center of b, the mean value of (b, a, b, c, d) in the five-point window is the filtered value of b, and other data are calculated in the same way.
[0057] Step S23: marking any well that meets the low reaction threshold or is higher than the noise threshold as a bad well, and excluding the bad well in all subsequent calculations.
[0058] Step S3: calculating the background value of each dot array in each frame, and calculating the background value of each dot array in each frame based on its position information, wherein the background value is based on the mean value of all wells in the annular region surrounding the dot array, excluding bad wells, as shown in FIG. 5, wherein the red circle is the dot array region, and the two blue dashed lines are the background region. Figure 4
[0059] In this embodiment, preferably, in step S3, the annular region takes the center coordinate of the dot array as the center, takes the times of the dot array radius as the inner ring radius, and takes the inner ring radius plus a preset expansion distance R as the outer ring radius. In this embodiment, the expansion distance R is usually related to the chip size and the dot array inoculation, and is set by the experimental personnel when the chip is set. If not set, the half of the dot array radius can be used as the default, which can roughly ensure that the number of wells in the dot array is comparable to the number of wells in the annular region.
[0060] Step S4: marking the effective wells in the dot array according to the background value and calculating the dot array signal of each frame.
[0061] In this embodiment, preferably, in step S4, in the circular dot array region, the wells in the dot array that are higher than the background value are marked as effective wells, and the calculation formula of the signal of the dot array 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 and negative polarity of an electronic microarray chip based on an ISFET sensor, characterized in that: Includes the following steps: 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 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.