CN111982992B - Method and system for automatic detection of glucose with wide range and high precision - Google Patents

Abstract

The invention discloses a wide-range high-precision automatic detection method for glucose. On the basis that a self-made Prussian blue bio-enzyme electrode has a wide-range linearization characteristic on glucose concentration detection, the sample injection amount is automatically adjusted according to an autonomous recognition detection area, and wide-range high-precision detection under the condition that the glucose concentration range is unknown is realized. The method adopts a Prussian blue bio-enzyme electrode to react with microbial fermentation liquor in a special detection pool to generate microampere current, establishes a response signal and glucose concentration response equation by designing a microampere current detection circuit and filtering, calculates a measured value of glucose concentration, automatically identifies a detection concentration interval according to a measured value system, adjusts a sample volume set value V according to deviation, and automatically samples the sample V through a high-precision intelligent sample injection device, so that the concentration of an object to be detected in the detection pool is in the optimal response range of a sensing electrode, and the wide-range and high-precision automatic detection of the glucose is realized.

Description

Method and system for automatic detection of glucose with wide range and high precision

technical field

The invention relates to the field of microbial fermentation industry, and aims at the problem of online detection of the concentration of key components such as substrates, intermediate metabolites and products in the fermentation process, and provides a wide-range high-precision automatic detection method for glucose, which realizes the wide range of glucose under unknown concentration. The scope and accurate detection belong to the interdisciplinary technical field of biopharmaceuticals, communications and software.

Background technique

The microbial fermentation industry generally adopts an "extensive" production mode dominated by batch fermentation. During the production process, the concentration changes of substrates or products cannot be tracked in time. The understanding of the fermentation process is often in a "black box" state, and production operations are completely dependent on Due to the operating experience, the production efficiency is low and the environmental pollution is serious. Therefore, there is an urgent need to develop an online analytical instrument for the concentration of fermentation substrates and products in my country.

The detection of the concentration of each component in the fermentation process is very important. It can help people understand the fermentation process in real time and know the physiological status of the relevant microorganisms. Fermentation control.

At present, the methods used to detect the concentration of each component in the fermentation process mainly include: titration color method, high performance liquid chromatography, biosensor method, etc., which have been widely used. Biosensors can convert the concentration of reaction components into identifiable physical signals such as optical signals, electrochemical signals, etc. After processing and amplifying the generated physical signals, by studying the changes of the signals, the concentration of fermentation components can be obtained. amount of change. This method has good selectivity for the analyte, high sensitivity, low cost, and easy miniaturization, so it is more favored by the fermentation process.

Through online analysis of the concentration of key components such as fermentation substrates, intermediate metabolites and products, the physiological state of cells can be reflected in real time. According to the physiological state of cells, the rules of cell growth and metabolism and phase characteristics can be revealed, so as to guide the real-time regulation of microbial fermentation process. The substrate can be fully utilized in the fermentation, and the synthesis efficiency of the product can be improved at the same time.

SUMMARY OF THE INVENTION

Aiming at the problems existing in the background technology, the present invention proposes a wide-range and high-precision automatic detection method and system for glucose.

Technical solutions:

The invention first discloses a wide-range high-precision automatic detection method for glucose, which comprises the following steps:

S1. The chemical reaction between the enzyme electrode and the substrate produces a current signal at the microamp level;

S2, the current signal is converted into a standard voltage signal;

S3. The digital filtering system filters the signal to obtain an effective AD value, and effectively eliminates various signal interferences in the detection;

S4, establish a concentration response equation;

S5, the voltage-based digital signal accurately measures the glucose concentration of the object to be tested;

S6, determine whether it is in the optimal concentration range, if yes, go to S7; otherwise, adjust the injection volume, and return to step S5;

S7. Obtain the final glucose concentration of the test substance.

Preferably, the specific steps of S2 are:

S2-1. The current signal is converted into a voltage signal through the I/V conversion circuit;

S2-2, the voltage signal is converted into a standard voltage signal through two-stage program-controlled amplification.

Preferably, the specific steps of S3 are:

S3-1. The standard voltage signal is converted into a digital signal through a 16-bit A/D conversion circuit;

S3-2. The digital signal is processed by digital filtering Y(n)=αX(n)+(1-α)Y(n-1) to obtain an effective AD value; α is a number less than 1 and greater than 0, X(n ) is the AD value actually collected this time, Y(n-1) is the AD value obtained last time, and Y(n) is the AD value obtained this time. Adding digital filtering can filter out the interference of random signals. The digital filtering uses the AD value of the current sampling and the AD value of the previous sampling to be weighted to obtain an effective AD value, so that the output signal of the previous time has a feedback effect on the signal of the next time.

Preferably, the steps for establishing the concentration response equation in S4 are:

S4-1, when the detection pool has only buffer, the AD value collected by S1-S3 is recorded as ADV ₀ ;

S4-2, inject the standard solution of volume V ₀ concentration C ₀ , carry out the AD value collected by S1-S3 and record it as ADV ₁ ;

S4-3. Establish a concentration response equation:

In the formula, y is the collected AD value, and x is the concentration c of the analyte.

More preferably, S4 also includes the step of checking the concentration response equation:

S4-4, inject the standard solution of volume V ₀ again, carry out the AD value that S1-S3 collects and record as ADV ₂ ;

S4-5. Calculate the concentration c of the analyte at this time according to the concentration response equation established in S4-3. If c∈[C ₀ -2%, C ₀ +2%], the concentration response equation is considered reliable; otherwise, the concentration The response equation fails, and S4-1-S4-5 are repeated to build the concentration response equation.

Preferably, the measuring step of the glucose concentration of the test object in S5 is:

S5-1, clean the pipetting needle, inject a certain volume of V ₁ of the liquid to be tested in the detection tank, and collect the AD value at this time and record it as ADV ₃ ;

S5-2. Substitute ADV ₃ as y into the corresponding equation of concentration established in S4-3 to obtain the theoretical concentration C ₁ =x of the liquid to be tested;

S5-3, the actual concentration C of the liquid to be tested:

In the formula, V ₀ is the volume of the standard solution.

Preferably, the Prussian blue bioelectrode detection chip has a good linear relationship with the reaction current within an appropriate concentration range because of its biological properties. The step of determining whether it is in the optimal concentration range in S6 is:

S6-1. Establish a linear relationship between the weak current of the enzyme electrode and different concentrations of the analyte;

S6-2. Divide the concentration of the analyte and the injection volume into different intervals according to the linear relationship: V ₁ , V ₂ , V ₃ are the volume of the injection volume, V ₁ >V ₂ >V ₃ , X ₀ , X ₁ , X ₂ , X ₃ is the optimal detection concentration node corresponding to the injection amount of the detection chip, X ₀ <X ₁ <X ₂ <X ₃ ;

When the injection volume is V ₁ , the optimal detection range of the chip is between X ₀ and X _1. When the injection volume is V ₂ , the optimal detection range of the chip is between X ₁ and X ₂ . When the sample size is V ₃ , the optimal detection range of the chip is between X ₂ and X ₃ ;

S6-3, the determination step S5 obtains the size of the concentration C and X ₁ :

(1) If C<X ₁ , it is considered to be in the optimal concentration range and ends;

(2) If C≥X ₁ , adjust the injection volume to V ₂ , and repeat S5 to obtain the concentration C′;

Determine the size of the obtained concentration C' and X ₂ :

(3) If C'<X ₂ , it is considered to be in the optimal concentration range and ends;

(4) If C′≥X ₂ , adjust the injection amount to V ₃ , and repeat S5 to obtain the concentration C″.

Preferably, the final glucose concentration of the analyte is obtained by taking the average of three consecutive measurements.

The invention also discloses a wide-range high-precision automatic detection system for glucose, including an enzyme electrode sensing system, a micro-amp current detection circuit, a data filtering acquisition system, a host, and a high-precision injection automatic control system:

The enzyme electrode is set in the detection cell, and chemically reacts with the substrate to generate a current signal of microampere level;

The microampere current detection circuit detects the current signal of the microampere level and converts it into a standard voltage signal;

The data filtering and acquisition system filters the standard voltage signal to effectively eliminate various signal interferences in the detection and achieve high-precision detection;

Based on the established concentration response equation, the host obtains the concentration data of the analyte according to the linear relationship between the concentration measurement value and the response current;

High-precision injection automatic control system, the control system independently identifies different concentration ranges, and automatically adjusts the injection volume according to the concentration range to ensure that the concentration of the analyte in the detection cell is within the optimal response range of the sensing electrode.

Preferably, it also includes an autonomous calibration system, which is used for automatically judging whether the enzyme activity is reduced during detection, and based on this, to determine whether to re-establish the corresponding concentration response equation, thereby improving the detection accuracy.

The beneficial effects of the present invention

A wide-range high-precision automatic detection method for glucose uses an electrochemical enzyme biosensor prepared by Prussian blue. The enzyme biosensor reacts with different concentrations of the components to be tested to generate microampere electrochemical signals, and the microamp current detection circuit converts the microampere level. The first-level current signal is converted into a standard voltage signal through the I/V and second-level program-controlled amplifying circuit, and then converted into a digital signal through a 16-bit A/D conversion circuit, and an effective AD value is obtained through digital filtering. The linear relationship is established to establish an equation, and the measured value of the component concentration is calculated. The control system independently identifies different concentration ranges, determines whether the measured value is within the optimal concentration range, and automatically adjusts the set value V of the injection volume according to the deviation to ensure the The concentration of the substance to be tested is distributed in the most suitable range of the detection chip, and the liquid to be tested is injected into the detection cell through the high-precision sampling device for detection, and the average value is obtained by multiple detections, thereby realizing a wide range of high-precision detection.

The Prussian blue biological enzyme electrode can detect glucose in a certain concentration range because of its detection characteristics, and the automatic detection method provided by the invention can expand the detection range of glucose concentration and improve the detection accuracy. Through the self-made Prussian blue biological enzyme electrode, the electrode sensing system, high-precision low-cost detection circuit, data filtering and acquisition system, independent calibration system, concentration response equation, and high-precision injection automatic device are designed to realize wide-range and high-precision detection of glucose.

The research of biological fermentation process is a huge project. Real-time monitoring of the fermentation process will provide data support for the research of biological fermentation, which can make the research more in-depth and transparent, provide a basis for advanced fermentation process control, and facilitate the fermentation process. Carry out feedback control to create a better reaction environment for biochemical reactions in biological fermentation.

Description of drawings

FIG. 1 is a functional module design diagram of the detection method of the present invention.

Fig. 2 is the self-prepared sensor chip of the present invention

3 is a block diagram of the overall structure of the microamp current detection circuit of the present invention

FIG. 4 is a logic diagram of automatically adjusting the injection volume of the present invention.

Marked as: 1-insulating layer, 2-working layer, 3-conductive layer, 4-reference layer, 5-polyethylene terephthalate (PET) substrate, 6-integrated sensor chip, 7- -reference voltage circuit, 8-I2C circuit, 9-I/V conversion circuit, 10-signal amplifier, 11-noise suppression circuit, 12-digital I/O port, 13-storage circuit, 14-main chip, 15- Clock, 16-16-bit ADC, 17-power, 18-485 circuit, 19-host

Detailed ways

Below in conjunction with embodiment, the present invention is further described, but protection scope of the present invention is not limited to this:

The present invention discloses a wide-range and high-precision automatic detection method for glucose. With reference to Fig. 1, it includes the following steps:

S1. The chemical reaction between the enzyme electrode and the substrate produces a current signal at the microamp level;

S2, the current signal is converted into a standard voltage signal;

S3. The digital filtering system filters the signal to obtain an effective AD value, and effectively eliminates various signal interferences in the detection;

S4, establish a concentration response equation;

S5, the voltage-based digital signal accurately measures the glucose concentration of the object to be tested;

S6, determine whether it is in the optimal concentration range, if yes, go to S7; otherwise, adjust the injection volume, and return to step S5;

S7. Obtain the final glucose concentration of the test substance.

In a preferred embodiment, the enzyme electrode in S1 is a Prussian blue biological enzyme electrode. According to the accurate identification characteristics of the regular nanocrystalline structure of the Prussian blue material for a wide linear range of glucose concentration, the three electrodes in the sensing system are collected by screen printing technology. It becomes a miniature sensor chip; S2 adopts a micro-amp current detection circuit to collect the current signal of the micro-amp level generated by the enzyme electrode, and converts it into a standard voltage signal through the designed I/V conversion circuit and amplifying circuit, and passes the 16-bit high-precision A/ The D conversion circuit realizes accurate signal detection and conversion of microampere current; in S3, a data filtering and acquisition system is designed to filter the signals collected by the detection circuit, effectively eliminating various signal interference in the detection, and realizing high-precision detection; in S4, the host is established Concentration response equation: According to the linear relationship between the concentration measurement value and the response current, the concentration response equation is established according to the independent calibration, and the equation is verified to ensure the reliability of the equation; in S6, the high-precision injection automatic control system independently identifies different concentration intervals , automatically adjust the injection volume according to the concentration interval, ensure that the concentration of the analyte in the detection cell is within the optimal response range of the sensing electrode, and realize the wide-range and high-precision detection of glucose.

2, the integrated sensor chip 6 is used as a Prussian blue bio-enzyme electrode, and a self-made Prussian blue bio-electrode detection chip is used, including an insulating layer 1, a working layer 2, a conductive layer 3, a reference layer 4, a substrate 5, and a conductive layer 3 Designed as a three-electrode printed chip configuration, the Prussian blue (working electrode-working layer 2), carbon paste (counter electrode), and AgCl (reference electrode-reference layer 4) were miniaturized and integrated into On the same organic support-substrate 5, in a preferred embodiment, the substrate 5 is a polyethylene terephthalate (PET) substrate; the enzyme is attached to the working electrode, and chemically reacts with the substrate to generate microampere level. When different concentrations of substrates react with the Prussian blue bioelectrode detection chip, different magnitudes of microampere currents will be generated. Because of its biological characteristics, the Prussian blue bioelectrode detection chip will have a good reaction with the reaction current within a suitable concentration range. Linear relationship, the concentration of the component to be tested can be divided into different intervals according to its detection characteristics.

3, the glucose wide-range high-precision automatic detection system includes a reference voltage circuit 7, an I2C circuit 8, an I/V conversion circuit 9, a signal amplifier 10, a noise suppression circuit 11, a digital I/O port 12, a storage circuit 13, Main chip 14 , clock 15 , 16-bit ADC16 , power supply 17 , 485 circuit 18 , host 19 . Among them: digital I/O port 12, storage circuit 13, main chip 14, clock 15, 16-bit ADC16 form MCU; I/V conversion circuit 9, signal amplifier 10, noise suppression circuit 11 are used to react the integrated sensor chip 6 The generated microampere current signal passes through the I/V conversion circuit and signal amplifier, noise suppression, and then the 16-bit ADC16 collects the digital signal at this time, and transmits it to the host computer 19 through the 485 circuit 18, and is tested in the host computer 19. The glucose concentration of the substance was detected.

判断C′₁与X₁的大小关系：若C′₁小于X₁，则重复上述两次清洗取样，计算出浓度分别为C″₁、C″′₁，计算待测液的浓度C＝(C′₁+C″₁+C″′₁)/3，再清洗结束；若C′₁大于X₁，调整进样量为V₂，清洗，移液针抽取V₂体积的未知浓度的待测液进行检测，计算出浓度为C₂，根据V₀、V₂和C₂的关系得出待测液的实际浓度为：

判断C′₂与X₂的大小关系，若C′₂小于X₂，重复上述两次清洗取样，计算出浓度分别为C″₂、C″′₂，计算待测液的浓度C＝(C′₂+C″₂+C₂″′)/3，再清洗结束；若C₂大于X₂，调整进样量为V₃，清洗，移液针抽取V₃体积的未知浓度的待测液进行检测，计算出浓度为C₃，根据V₀、V₂和C₃的关系得出待测液的实际浓度为：

重复上述两次清洗取样，计算出浓度分别为C″₃、C″′₃，计算待测液的浓度C＝(C′₃+C″₃+C₃″′)/3，再清洗结束。Figure 4 shows the logic diagram of automatically adjusting the injection volume. The pipetting needle extracts V ₁ volume of the liquid to be tested for detection, and the concentration is calculated as C ₁ . According to the relationship between V ₀ , V ₁ and C ₁ , the actual concentration of the liquid to be tested is:

Determine the relationship between C′ ₁ and X ₁ : if C′ ₁ is less than X ₁ , repeat the above two cleaning and sampling, calculate the concentrations as C″ ₁ and C″′ ₁ respectively, and calculate the concentration of the liquid to be tested C=( C′ ₁ +C″ ₁ +C″′ ₁ )/3, the cleaning is finished again; if C′ ₁ is greater than X ₁ , adjust the injection volume to V ₂ , clean, and pipette the needle to extract V ₂ volume of unknown concentration Measure the liquid for detection, and calculate the concentration as C ₂ . According to the relationship between V ₀ , V ₂ and C ₂ , the actual concentration of the liquid to be tested is:

Judging the relationship between C' ₂ and X ₂ , if C' ₂ is less than X ₂ , repeat the above two cleaning and sampling, calculate the concentrations as C" ₂ and C"' ₂ respectively, and calculate the concentration of the liquid to be tested C=(C ′ ₂ +C″ ₂ +C ₂ ″′)/3, and the cleaning is over; if C ₂ is greater than X ₂ , adjust the injection volume to V ₃ , clean, and the pipette needle extracts V ₃ volume of the unknown concentration of the liquid to be tested Carry out detection and calculate the concentration as C ₃ . According to the relationship between V ₀ , V ₂ and C ₃ , the actual concentration of the liquid to be tested is obtained as:

Repeat the above two cleaning and sampling, calculate the concentrations as C″ ₃ and C″′ ₃ respectively, calculate the concentration of the liquid to be tested C=(C′ ₃ +C″ ₃ +C ₃ ″′)/3, and then finish cleaning.

The present invention will be further described below in conjunction with specific practical operations.

According to the experiment, the segmental relationship between the injection volume and the concentration of the Prussian blue bioelectrode detection chip for glucose detection is as follows: when the injection volume is 50 μl, the optimal detection range of the chip is between 0.2 and 5 g/L. When the sample volume is 25 μl, the optimal detection range of the chip is between 5 and 20 g/L, and when the sample injection volume is 5 μl, the optimal detection range of the chip is between 20 and 100 g/L.

The glucose solution reacts with the enzyme electrode in the detection cell to generate a weak microampere current, which is converted into a voltage signal through the I/V conversion circuit of the detection circuit, and the voltage signal is converted into a standard voltage signal through two-stage program-controlled amplification. The /D conversion circuit is converted into a digital signal, and the digital signal is processed by digital filtering Y(n)=αX(n)+(1-α)Y(n-1) to obtain an effective AD value.

再次注入相同体积的葡萄糖标准液采集到的2141.5值代入已经建立的浓度响应方程计算出浓度6.04g/L，6.04g/L在标准液浓度6g/L的±2％误差以内，认为浓度响应方程可靠。According to the AD value collected by the control system, it is 2583 when there is only buffer in the detection pool, and 2144.6 when there is a 50uL volume of glucose standard solution with a known concentration of 6g/L, and the concentration response equation is established.

The 2141.5 value collected by injecting the same volume of glucose standard solution again is substituted into the established concentration response equation to calculate the concentration of 6.04g/L, 6.04g/L is within the ±2% error of the standard solution concentration of 6g/L, it is considered that the concentration response equation reliable.

After the concentration-response equation is established successfully, clean it, and extract a volume of 50uL of unknown concentration of glucose to be tested by the pipette. The calculated concentration is 10.23g/L. According to the relationship between V ₀ , V ₁ and C ₁ , the test solution is obtained. The actual concentration of the liquid is: 10.23g/L;

10.23 is greater than 5, adjust the injection volume to 25uL, clean, and extract 25uL volume of the unknown concentration of the liquid to be tested with the pipette for detection, and the calculated concentration is 22.50g/L. According to the relationship between V ₀ , V ₂ and C ₂ The actual concentration of the liquid to be tested is: 45.00g/L;

If 45.00 is greater than 20, adjust the injection volume to 5uL, wash, and extract 5uL volume of the unknown concentration of the liquid to be tested with the pipette needle for detection. The calculated concentration is 6.01g/L. According to the relationship between V ₀ , V ₂ and C ₃ The actual concentration of the liquid to be tested is 60.1g/L. Repeat the above two cleaning and sampling, and the calculated concentrations are 60.5g/L and 59.8g/L respectively. Calculate the concentration of the liquid to be tested C=(60.1+60.5+59.8 ′)/3, and then cleaning is completed.

The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which the present invention pertains can make various modifications or additions to the described specific embodiments or substitute in similar manners, but will not deviate from the spirit of the present invention or go beyond the definitions of the appended claims range.

Claims (9)

1. A wide-range high-precision automatic detection method for glucose is characterized by comprising the following steps:

s1, carrying out chemical reaction on the enzyme electrode and the substrate to generate a microampere current signal;

s2, converting the current signal into a standard voltage signal;

s3, filtering the signal by the digital filtering system to obtain an effective AD value, and effectively eliminating various signal interferences in detection;

s4, establishing a concentration response equation;

s5, accurately measuring the glucose concentration of the object to be measured based on the digital signal of the voltage;

s6, judging whether the concentration is in the optimal concentration range, if so, carrying out S7; otherwise, adjusting the sample volume and returning to the step S5; the step of determining whether the concentration is within the optimum concentration range in S6 is:

s6-1, establishing a linear relation between the weak current of the enzyme electrode and different concentrations of the object to be detected;

s6-2, dividing the concentration and the sample volume of the object to be detected into different intervals according to a linear relation: v₁，V₂，V₃For sample volume, V₁>V₂>V₃，X₀，X₁，X₂，X₃For detecting the optimum detection concentration node of the chip corresponding to the sample amount, X₀<X₁<X₂<X₃；

When the sampling amount is V₁Then, the optimum concentration range for chip detection is X₀～X₁When the sample volume is V₂Then, the optimum concentration range for chip detection is X₁～X₂When the sample volume is V₃Then, the optimum concentration range for chip detection is X₂～X₃To (c) to (d);

s6-3, determining the concentrations C and X obtained in step S5₁The size of (2):

(1) if C is less than X₁If the concentration is in the optimal concentration range, the method is considered to be ended;

(2) if C is greater than or equal to X₁Then adjust the sampling amount to V₂Repeating S5 to obtain a concentration C';

judging to obtain the concentrations C' and X₂The size of (2):

(3) if C' < X₂If so, determining that the concentration is in the optimal concentration range and ending;

(4) if C' is not less than X₂Then adjust the sampling amount to V₃Repeating S5 to obtain a concentration C';

and S7, obtaining the final glucose concentration of the analyte.

2. The method according to claim 1, wherein the specific steps of S2 are:

s2-1, converting the current signal into a voltage signal through an I/V conversion circuit;

and S2-2, converting the voltage signal into a standard voltage signal through two-stage program control amplification.

3. The method according to claim 1, wherein the specific steps of S3 are:

s3-1, converting the standard voltage signal into a digital signal through a 16-bit A/D conversion circuit;

s3-2, processing the digital signal by digital filtering Y (n) ═ α x (n) +(1- α) Y (n-1) to obtain an effective AD value, wherein: alpha is a number smaller than 1 and larger than 0, X (n) is the AD value actually acquired this time, Y (n-1) is the last AD value obtained last time, and Y (n) is the AD value obtained this time.

4. The method of claim 1, wherein the step of establishing the concentration response equation in S4 comprises:

s4-1, when the detection cell only contains buffer solution, the AD value collected by S1-S3 is recorded as ADV₀；

S4-2, injection volume V₀Concentration C₀The AD value obtained in S1-S3 of the standard solution of (1) is ADV₁；

S4-3, establishing a concentration response equation:

in the formula, y is the collected AD value, and x is the concentration c of the substance to be detected.

5. The method of claim 4, wherein S4 further comprises the step of verifying the concentration response equation:

s4-4, reinjection of volume V₀The AD value obtained in S1-S3 of the standard solution of (1) is ADV₂；

S4-5, calculating the concentration c of the object to be measured according to the concentration response equation established in S4-3, and if c is∈[C₀-2％，C₀+2％]The concentration response equation is considered to be reliable; otherwise, the concentration response equation is considered to fail, and S4-1-S4-5 is repeated to establish the concentration response equation.

6. The method according to claim 4, wherein the step of measuring the glucose concentration of the analyte in S5 comprises:

s5-1, cleaning the liquid-transfering needle, and injecting a certain volume V into the detection pool₁Collecting the AD value of the solution to be detected and recording as ADV₃；

S5-2, ADV₃Substituting the y into a concentration corresponding equation established by S4-3 to obtain the theoretical concentration C of the liquid to be detected₁＝x；

S5-3, and the actual concentration C of the solution to be detected:

in the formula, V₀Is the volume of the standard solution.

7. The method of claim 1, wherein the final glucose concentration of the analyte is obtained by averaging 3 consecutive measurements.

8. The wide-range high-precision automatic glucose detection system is characterized by comprising an enzyme electrode sensing system, a microampere current detection circuit, a data filtering and collecting system, a host and a high-precision injection automatic control system:

the enzyme electrode is arranged in the detection cell and generates microampere-level current signals by chemical reaction with the substrate;

the microampere current detection circuit detects microampere current signals and converts the microampere current signals into standard voltage signals;

the data filtering acquisition system filters the standard voltage signal, effectively eliminates various signal interferences in detection and realizes high-precision detection;

the host computer obtains concentration data of the object to be measured according to the linear relation between the concentration measurement value and the response current based on the established concentration response equation;

the control system automatically identifies the concentration interval in which the concentration of the object to be detected is located, and automatically adjusts the sample injection amount according to the concentration interval to ensure that the concentration of the object to be detected in the detection pool is in the optimal response range of the sensing electrode.

9. The system of claim 8, further comprising an autonomous calibration system for automatically determining whether the enzyme activity is decreased during the test, and thereby determining whether to re-establish the corresponding concentration response equation, thereby improving the accuracy of the test.

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