A method and apparatus for detecting uric acid concentration

Abstract

The application relates to the technical field of uric acid concentration detection, in particular to a uric acid concentration detection method and device. A uric acid detection method comprises the following steps: obtaining a uric acid oxidation potential and an acetylaminophenol oxidation potential according to a reaction electrode area state; controlling a first working electrode and a second working electrode to collect a uric acid total current signal and an interfering substance current signal according to a preset first voltage application range, a preset second voltage application range, the uric acid oxidation potential and the acetylaminophenol oxidation potential; analyzing a detection sample reaction temperature and a sensor group output signal according to the uric acid total current signal and the interfering substance current signal to obtain a uric acid concentration value; a hardware non-enzyme electrode design reduces manufacturing cost, avoids enzyme activity fluctuation and improves detection precision; a signal collection double-voltage strategy separates target and interference signals, and ensures signal purity; the scheme is convenient to operate, controllable in cost and suitable for popularization in multiple scenes.

Description

Technical Field

[0001] This invention relates to the field of uric acid concentration detection technology, and in particular to a method and apparatus for uric acid concentration detection. Background Technology

[0002] In the electrochemical detection of uric acid, reducing substances such as ascorbic acid can easily interfere with the detection results, and existing anti-interference technologies have significant limitations. One approach involves adding an anti-interference layer or channel containing ascorbic acid oxidase to the sensor reaction area. While this can eliminate ascorbic acid interference to some extent, it cannot completely remove it, and the introduction of the anti-interference enzyme increases the sensor manufacturing cost. Another approach involves coating the sensor surface with a low oxidation potential conductive medium and obtaining the signal by applying an oxidation potential. However, because the potential exceeds the oxidation potential of the interfering substances, it is still difficult to completely eliminate the interference from reducing substances. Furthermore, the conductive medium is prone to oxidation-reduction reactions over a long period of time, affecting the stability of the sensor and increasing manufacturing processes and costs. In summary, existing technologies struggle to balance anti-interference effectiveness, detection accuracy, stability, and cost. Developing a uric acid concentration detection method that can effectively eliminate interference, has a simple process, low cost, high sensitivity, and fast detection speed is of significant practical importance. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a method and apparatus for detecting uric acid concentration.

[0004] A method for detecting uric acid concentration is applied to a uric acid concentration detection device, the device comprising an impedance electrode, a uric acid instrument, a first working electrode, a second working electrode, and a sensor group; a reaction electrode region is formed between the impedance electrode, the uric acid instrument, the first working electrode, the second working electrode, and the sensor group; the method for detecting uric acid concentration includes the following steps: acquiring the state of the reaction electrode region; acquiring the uric acid oxidation potential and the acetaminophen oxidation potential based on the state of the reaction electrode region; controlling the first and second working electrodes to acquire the total uric acid current signal and the interfering substance current signal according to a preset first voltage application range, a preset second voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential; acquiring the reaction temperature of the test sample and the output signal of the sensor group; and analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the total uric acid current signal and the interfering substance current signal to obtain the uric acid concentration value.

[0005] Further, the step of obtaining the uric acid oxidation potential and acetaminophen oxidation potential based on the state of the reaction electrode region includes: analyzing the state of the reaction electrode region; when the state of the reaction electrode region is that the blood sample has reached the reaction electrode region, applying a sinusoidal AC signal to the reaction electrode region by controlling the impedance electrode according to a preset working frequency; under the sinusoidal AC signal application state, acquiring real-time impedance data according to a preset acquisition frequency; performing time-domain analysis on the real-time impedance data to obtain the impedance change rate; determining whether the impedance change rate is less than a preset impedance change rate threshold; when the impedance change rate is less than the impedance change rate threshold, acquiring the uric acid oxidation potential and acetaminophen oxidation potential.

[0006] Further, the step of controlling the first and second working electrodes to acquire the total uric acid current signal and the interfering substance current signal according to the preset first voltage application range, the preset second voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential includes: generating a first voltage application strategy based on the first voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential; controlling the uric acid instrument to apply a pre-voltage to the first working electrode according to the first voltage application strategy; acquiring the ascorbic acid oxidation potential; generating a second voltage application strategy based on the second voltage application range, the first voltage application strategy, the uric acid oxidation potential, and the ascorbic acid oxidation potential; controlling the uric acid instrument to apply a decreasing voltage to the second working electrode according to the second voltage application strategy; acquiring the pre-voltage application state and analyzing the pre-voltage application state according to the preset first application duration threshold; when the pre-voltage application state reaches the first application duration threshold, acquiring the decreasing voltage application state and analyzing the decreasing voltage application state according to the preset second application duration threshold; when the decreasing voltage application state reaches the second application duration threshold, controlling the first and second working electrodes to acquire the total uric acid current signal and the interfering substance current signal according to the preset acquisition frequency.

[0007] Furthermore, the step of analyzing the reaction temperature of the test sample and the sensor group output signal based on the total uric acid current signal and the interfering substance current signal to obtain the uric acid concentration value includes: correcting the total uric acid current signal and the interfering substance current signal according to a preset correction range to obtain a correction current signal; acquiring sensor group performance calibration data and reaction electrode area temperature data; and analyzing the test sample reaction temperature and sensor group output signal based on the correction current signal, sensor group performance calibration data, and reaction electrode area temperature data to obtain the uric acid concentration value.

[0008] Further, the step of correcting the total uric acid current signal and the interfering substance current signal according to a preset correction range to obtain a corrected current signal includes: acquiring the width of the first working electrode and the width of the second working electrode; generating a correction factor based on the correction range, the width of the first working electrode, and the width of the second working electrode; and correcting the total uric acid current signal and the interfering substance current signal according to a preset theoretical current signal and the correction factor to obtain a corrected current signal.

[0009] Furthermore, the step of analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the calibration current signal, sensor group performance calibration data, and reaction electrode area temperature data to obtain the uric acid concentration value includes: analyzing the sensor group performance calibration data based on a preset number of days of use to obtain a sensitivity attenuation coefficient; analyzing the reaction electrode area temperature data based on a preset reaction time to obtain a temperature compensation coefficient; performing type analysis on a preset test sample to obtain a sample dilution factor; and analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the calibration current signal, sample dilution factor, sensitivity attenuation coefficient, and temperature compensation coefficient to obtain the uric acid concentration value.

[0010] Furthermore, the step of correcting the total uric acid current signal and the interfering substance current signal according to the preset theoretical current signal and correction factor to obtain a corrected current signal includes: determining whether the interfering substance current signal is less than or equal to the theoretical current signal; if the interfering substance current signal is less than or equal to the theoretical current signal, then generating a corrected current signal based on the total uric acid current signal; otherwise, correcting the total uric acid current signal and the interfering substance current signal according to the correction factor and the theoretical current signal to obtain a corrected current signal.

[0011] Furthermore, a uric acid concentration detection device includes a control module and an impedance electrode, a uric acid instrument, a first working electrode, a second working electrode, and a sensor group electrically connected to the control module; a reaction electrode region is formed between the impedance electrode, the uric acid instrument, the first working electrode, the second working electrode, and the sensor group; the control module is used to perform a uric acid concentration detection method as described in any one of the above.

[0012] Furthermore, the uric acid concentration detection device also includes an insulating substrate, on which the first working electrode and the second working electrode are printed; the raw materials of the first working electrode and the second working electrode include conductive ink, and the raw material of the impedance electrode includes conventional carbon ink.

[0013] Furthermore, the conductive ink is a conductive carbon ink doped with a water-soluble redox conductive medium.

[0014] In the technical solution of this invention, an enzyme-free electrode design is adopted in terms of hardware, eliminating the need for coating with anti-interference enzyme solution and conductive medium coating. This reduces costs while avoiding detection deviations caused by enzyme activity fluctuations, thus improving detection accuracy. In the signal acquisition stage, a dual-voltage strategy is used to accurately separate the target current signal from the interference current signal: the first voltage range activates the uric acid oxidation reaction and shields high-potential interference such as acetaminophen; the second voltage range specifically captures reducing interference such as ascorbic acid and dopamine, ensuring signal purity. When calculating the concentration, the reaction temperature of the test sample and the output signal of the sensor group are combined to accurately subtract interference signals, offset the influence of temperature on detection, correct sensor output deviations, and improve the accuracy and reliability of uric acid concentration detection. The overall solution is suitable for clinical sample scenarios, is easy to operate, and has controllable costs, making it suitable for promotion and application in various scenarios such as home self-testing and primary healthcare. Attached Figure Description

[0015] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0016] Figure 1 This is a first flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0017] Figure 2 This is a second flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0018] Figure 3 This is a third flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0019] Figure 4 This is a fourth flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0020] Figure 5 This is a fifth flowchart of a method for detecting uric acid concentration provided in an embodiment of the present invention;

[0021] Figure 6 The sixth flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0022] Figure 7 The seventh flowchart of a uric acid concentration detection method provided in an embodiment of the present invention;

[0023] Figure 8 This is a schematic diagram of the structure of a uric acid concentration detection device provided in an embodiment of the present invention;

[0024] Figure 9 This is a schematic diagram of the reaction electrode region of a uric acid concentration detection device provided in an embodiment of the present invention;

[0025] In the attached diagram, 1-control module; 2-impedance electrode; 3-uric acid instrument; 4-first working electrode; 5-second working electrode; 6-sensor group; 7-insulating substrate; 8-conductive wire layer; 9-reference electrode; 10-sample suction electrode; 11-sample suction channel layer; 12-hydrophilic membrane layer; 121-vent hole. Detailed Implementation

[0026] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" or "having" and any variations thereof are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0027] For ease of understanding, the specific process of the embodiments of the present invention is described below. Please refer to [link / reference]. Figure 1 One embodiment of a uric acid concentration detection method according to the present invention includes:

[0028] A method for detecting uric acid concentration is applied to a uric acid concentration detection device, the uric acid concentration detection device including an impedance electrode 2, a uric acid instrument 3, a first working electrode 4, a second working electrode 5, and a sensor group 6; a reaction electrode region is formed between the impedance electrode 2, the uric acid instrument 3, the first working electrode 4, the second working electrode 5, and the sensor group 6, and the uric acid concentration detection method includes the following steps:

[0029] 101. Obtain the state of the reaction electrode region;

[0030] In this embodiment, the electrode surface of sensor group 6 does not need to be coated, glued, or screen-printed with anti-interference enzyme solution and conductive medium coating. Through the enzyme-free design, the enzyme coating process is eliminated (reducing 3-4 production steps) and the detection deviation caused by enzyme activity fluctuations is avoided.

[0031] 102. The oxidation potential of uric acid and the oxidation potential of acetaminophen are obtained based on the state of the reaction electrode region;

[0032] 103. Based on the preset first voltage application range, the preset second voltage application range, the uric acid oxidation potential and the acetaminophen oxidation potential, the first working electrode 4 and the second working electrode 5 are controlled to collect the total uric acid current signal and the interference substance current signal.

[0033] In this embodiment, under the first voltage application range, the first working electrode 4 only activates the uric acid oxidation reaction (including uric acid signal + trace noise), and acetaminophen (a common high-potential interference in clinical practice) does not react (interference current) because the oxidation potential is not reached, thus shielding this type of interference; under the second voltage application range, the second working electrode 5 only responds to reducing interference such as ascorbic acid and dopamine, and uric acid does not respond, thus achieving dedicated capture of interference signals;

[0034] 104. Obtain the reaction temperature of the test sample and the output signal of the sensor group;

[0035] 105. Analyze the reaction temperature of the test sample and the output signal of the sensor group based on the total uric acid current signal and the current signal of interfering substances to obtain the uric acid concentration value;

[0036] In this embodiment, the uric acid concentration is calculated by comprehensively analyzing the total uric acid current signal and the current signal of interfering substances, combined with the reaction temperature of the detection sample and the output signal of the sensor group. This can accurately deduct the interference signal, offset the influence of temperature on the detection, correct the sensor output deviation, and improve the accuracy and reliability of uric acid concentration detection.

[0037] In this embodiment, an enzyme-free electrode design is adopted in the hardware, eliminating the need for anti-interference enzyme solution and conductive medium coating. This reduces costs while avoiding detection deviations caused by enzyme activity fluctuations, thus improving detection accuracy. In the signal acquisition stage, a dual-voltage strategy is used to accurately separate the target current signal from the interference current signal: the first voltage range activates the uric acid oxidation reaction and shields high-potential interference such as acetaminophen; the second voltage range specifically captures reducing interference such as ascorbic acid and dopamine, ensuring signal purity. When calculating the concentration, the reaction temperature of the test sample and the output signal of the sensor group are combined to accurately subtract interference signals, offset the influence of temperature on detection, correct sensor output deviations, and improve the accuracy and reliability of uric acid concentration detection. The overall solution is suitable for clinical sample scenarios, is easy to operate, and has controllable costs, making it suitable for promotion and application in various scenarios such as home self-testing and primary healthcare.

[0038] Please see Figure 2 A second embodiment of a uric acid concentration detection method according to the present invention includes:

[0039] 201. Analyze the state of the reaction electrode region;

[0040] 202. When the state of the reaction electrode area is that the blood sample has arrived in the reaction electrode area, the impedance electrode 2 is controlled to apply a sinusoidal AC signal to the reaction electrode area according to the preset working frequency.

[0041] In this embodiment, a preset sensing mechanism is used to confirm whether the blood sample has arrived and initially covered the reaction electrode area, thus avoiding the initiation of subsequent detection when there is no sample or the sample has not contacted the electrode; an infrared pair is embedded in the sampling channel near the reaction area, and the light path is blocked when the blood sample (light-shielding) passes through, and an "sample arrived" electrical signal is output (response time <10ms).

[0042] In another embodiment, a small DC voltage (e.g., 0.05V) is pre-applied between the reaction electrode and the reference electrode, and the electrode space is filled with air (impedance ≈ 10) before the blood sample arrives. 12 (Ω), upon arrival, the blood sample was an electrolyte solution (resistance suddenly dropped to 10). 3 ~10 5 Ω), through impedance abrupt change (from >10 8 Ω decreased to <10 6 Ω) indicates that the sample has arrived, providing a start signal for subsequent impedance monitoring;

[0043] 203. Under the condition of applying a sinusoidal AC signal, collect real-time impedance data according to the preset acquisition frequency;

[0044] In this embodiment, the sampling frequency is 100~500Hz (preferably 200Hz), that is, impedance data (including resistance component R and reactance component X) is collected every 5ms, and the impedance magnitude is calculated. High-frequency acquisition can capture subtle dynamics of blood sample diffusion (such as fluctuations in edge infiltration).

[0045] 204. Perform time-domain analysis on the real-time impedance data to obtain the impedance change rate;

[0046] 205. Determine whether the rate of change of impedance is less than the preset threshold for the rate of change of impedance;

[0047] 206. When the rate of change of impedance is less than the threshold of the rate of change of impedance, the uric acid oxidation potential and the acetaminophen oxidation potential are obtained.

[0048] In this embodiment, when the impedance change rate is ≤5% / s (impedance change rate threshold), it is determined that the sample stably covers the electrode and the interface state is constant. At this time, the "detection ready" signal is triggered, and the system begins to acquire the uric acid oxidation potential and acetaminophen oxidation potential, providing a parameter basis for the subsequent first voltage application strategy and ensuring that the voltage window accurately locks the target substance.

[0049] In this embodiment, the reliability of uric acid detection is improved by monitoring the state of the blood sample in the reaction electrode area; invalid detection is avoided by recognizing the arrival of the blood sample; after the blood sample arrives, the impedance data of the sinusoidal AC signal is collected, and the impedance change rate is obtained by time-domain analysis; based on the impedance change rate, it is determined that the blood sample stably covers the electrode, triggering detection readiness, ensuring accurate acquisition of subsequent oxidation potential, and providing reliable parameters for voltage strategy.

[0050] Please see Figure 3 A third embodiment of a uric acid concentration detection method according to the present invention includes:

[0051] 301. A first voltage application strategy is generated based on the first voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential;

[0052] In this embodiment, the first voltage is applied in the range of 0.3~0.6V, preferably in the range of 0.32~0.38V;

[0053] 302. The uric acid instrument 3 is controlled to apply a pre-voltage to the first working electrode 4 according to the first voltage application strategy;

[0054] In this embodiment, the first working electrode 4 is used to measure the total current signal of uric acid, but cannot measure the interference signal of acetaminophen. Therefore, the first voltage application strategy is to apply a voltage to the first working electrode 4 that is slightly greater than the uric acid oxidation potential and lower than the acetaminophen oxidation potential.

[0055] 303. Obtain the oxidation potential of ascorbic acid;

[0056] 304. A second voltage application strategy is generated based on the second voltage application range, the first voltage application strategy, the uric acid oxidation potential, and the ascorbic acid oxidation potential;

[0057] In this embodiment, the second voltage is applied in the range of 0.1~0.25V, preferably in the range of 0.2~0.25V;

[0058] 305. According to the second voltage application strategy, the uric acid instrument 3 applies a decreasing voltage to the second working electrode 5;

[0059] In this embodiment, after the blood sample enters the aspiration channel through the aspiration orifice and reaches the reaction electrode area, after a certain reaction time, the uric acid instrument 3 will simultaneously apply a voltage of a certain potential to the first working electrode 4 and the second working electrode 5. The second working electrode 5 is used to measure the total interference signal of reducing interfering substances such as ascorbic acid. It not only subtracts the interference signal of ascorbic acid, but also the interference signals of dopamine, levodopa, etc. Therefore, the second voltage application strategy is that the voltage applied to the second working electrode 5 should be slightly greater than the oxidation potential of ascorbic acid and lower than the oxidation potential of uric acid, wherein the voltage applied to the first working electrode 4 should be greater than the voltage applied to the second working electrode 5.

[0060] 306. Obtain the pre-voltage application state and analyze the pre-voltage application state according to the preset first application duration threshold;

[0061] 307. When the pre-voltage application state reaches the first application duration threshold, the falling voltage application state is obtained, and the falling voltage application state is analyzed according to the preset second application duration threshold.

[0062] In this embodiment, the first application duration threshold for the pre-voltage applied to the first working electrode 4 is set to 45s; based on the fact that the uric acid oxidation reaction needs to go through the process of "diffusion → adsorption → electron transfer", the first 10s is the rapid reaction period, and after 30s it enters the stable period. 45s can ensure that the reaction is sufficient and there is no excessive consumption (the uric acid concentration on the electrode surface is stable).

[0063] 308. When the applied voltage reaches the second application duration threshold, the first working electrode 4 and the second working electrode 5 are controlled to acquire the total uric acid current signal and the interfering substance current signal according to the preset acquisition frequency.

[0064] In this embodiment, the second application duration threshold for the voltage drop applied to the second working electrode 5 is set to 60s. This is based on the fact that the oxidation reaction of interfering substances such as ascorbic acid is faster (reaching stability in 15s), and applying the voltage synchronously with the first working electrode 4 ensures that the reaction progress of the two electrodes is consistent, facilitating signal comparison and interference subtraction. Once both electrodes have reached the duration threshold, the total uric acid current signal and the interfering substance current signal are simultaneously acquired at a sampling frequency of 10~100Hz (preferably 50Hz), and the average value of 100 data points is taken as the final signal to reduce concentration calculation deviations caused by time differences (such as the influence of changes in sample diffusion rate on the signal).

[0065] In this embodiment, the voltage application and signal acquisition logic are optimized to achieve accurate interference suppression and efficient detection in uric acid detection. After the blood sample enters the reaction area, the uric acid instrument 3 applies pressure to the dual electrodes simultaneously: the second working electrode 5 uses a voltage slightly higher than the ascorbic acid oxidation potential but lower than the uric acid oxidation potential to accurately capture various reducing interference signals such as ascorbic acid and dopamine; the first working electrode 4 has a higher voltage to ensure that it only responds to the uric acid signal; at the same time, a voltage application duration threshold is set for the first working electrode 4 and the second working electrode 5 to ensure that the uric acid reaction is sufficient and the interfering substances are completely oxidized; the signal is then acquired synchronously and averaged to reduce time difference and noise error; this solution can comprehensively suppress interference, ensure signal stability, has good detection repeatability, adapt to complex blood sample scenarios, provide reliable technical support for accurate clinical uric acid detection, and has an efficient operation process that is easy to integrate into actual detection applications.

[0066] Please see Figure 4 A fourth embodiment of a uric acid concentration detection method according to the present invention includes:

[0067] Interference deduction under low uric acid conditions:

[0068] Table 1 shows the current signal acquired by the first working electrode 4 before calibration and the deviation caused by interference:

[0069] Table 1

[0070]

[0071] It should be noted that I1-1 to I1-6 represent the current detection results of the first working electrode 4 under the corresponding conditions in 6 tests. The standard deviation SD represents the average fluctuation of the current data set I1-1 to I1-6 relative to the mean. The coefficient of variation (CV (%)) is the ratio between the standard deviation and the mean, corresponding to the relative fluctuation of the data.

[0072] After adding the anti-interference electrode (i.e., the second working electrode 5), the interference current signal collected on the second working electrode 5 is shown in Table 2:

[0073] Table 2

[0074]

[0075] It should be noted that I2-1 to I2-6 represent the current detection results of the second working electrode 5 under the corresponding conditions in 6 detections.

[0076] Interference deduction under high uric acid conditions:

[0077] Table 3 shows the current signal acquired by the first working electrode 4 before calibration and the deviation caused by interference:

[0078] Table 3

[0079]

[0080] After adding the anti-interference electrode (second working electrode 5), the interference current signal collected on the second working electrode 5 is shown in Table 4:

[0081] Table 4

[0082]

[0083] 401. Correct the total uric acid current signal and the interfering substance current signal according to the preset correction range to obtain the corrected current signal;

[0084] In this embodiment, the function of the correction range is to set reasonable boundaries for the width of the first working electrode, the width of the second working electrode, and the correction factor generated therefrom, so as to ensure that the correction factor can effectively offset the difference in electrode width and processing error.

[0085] 402. Obtain sensor group performance calibration data and reaction electrode area temperature data;

[0086] In this embodiment, the sensor group performance calibration data is a quantitative record of the "initial state and attenuation law" of sensor group 6. The core includes the initial sensitivity and attenuation coefficient, which are used to calculate the "sensitivity attenuation coefficient" to compensate for the performance decline of the sensor after use. The temperature data of the reaction electrode area is collected by the NTC sensor (accuracy ±0.1℃) embedded in the reaction area. The core indicator is the average temperature throughout the reaction process, which is used to offset the low signal caused by low temperature.

[0087] 403. Analyze the reaction temperature of the test sample and the output signal of the sensor group based on the calibration current signal, sensor group performance calibration data and reaction electrode area temperature data to obtain the uric acid concentration value;

[0088] In this embodiment, by combining the calibration current signal, sensor performance data, and temperature data to calculate uric acid concentration, multiple errors can be reduced, detection accuracy can be improved, environmental and hardware differences can be adapted, and the needs of precise clinical detection can be met.

[0089] In this embodiment, by using the calibration range, reasonable boundaries are set for the electrode width and calibration factor, effectively offsetting differences in electrode width and processing errors, ensuring the reliability of the current signal calibration basis, and reducing detection deviations caused by hardware from the source. Secondly, by acquiring sensor group performance calibration data, the attenuation coefficient is calculated using the initial sensitivity and attenuation coefficient to accurately compensate for the performance degradation of the sensor after use. At the same time, temperature data of the reaction electrode area is collected, and the average temperature throughout the process is used as the core indicator to offset the influence of temperature on the signal. The uric acid concentration is calculated by combining the calibration current signal, sensor performance data, and temperature data, improving detection accuracy. It can adapt to different hardware differences and environmental changes, and is easy to operate, meeting the needs of accurate detection in multiple clinical scenarios.

[0090] Please see Figure 5 A fifth embodiment of a uric acid concentration detection method according to the present invention includes:

[0091] 501. Obtain the width of the first working electrode 4 and the width of the second working electrode 5 to obtain the width of the first working electrode and the width of the second working electrode.

[0092] In this embodiment, the width of the first working electrode 4 and the width of the second working electrode 5 are the same or different; the width of the first working electrode and the width of the second working electrode are the core parameters that determine the "effective reaction area" of the electrode. In electrochemical detection, the current signal intensity is positively correlated with the effective reaction area of ​​the electrode: the larger the width, the larger the contact area between the electrode and the sample, and the stronger the oxidation and reduction current at the same concentration.

[0093] 502. Generate a correction factor based on the correction range, the width of the first working electrode, and the width of the second working electrode;

[0094] In this embodiment, the correction factor is a key parameter for reducing the difference between the width of the first working electrode and the width of the second working electrode and the "processing error". Its essence is a proportional coefficient that unifies the signals of the first working electrode 4 and the second working electrode 5 to the same reference (standard width).

[0095] 503. Correct the total uric acid current signal and the current signal of interfering substances according to the preset theoretical current signal and correction factor to obtain the corrected current signal;

[0096] In this embodiment, by combining the theoretical current signal with the correction factor to correct the relevant current signal, interference and electrode width differences can be reduced, the accuracy of uric acid detection can be improved, hardware differences can be adapted, the operation is simple, and the needs of accurate detection in multiple clinical scenarios can be met.

[0097] In this embodiment, by quantifying electrode hardware parameters and dynamically correcting signals, the accuracy, compatibility, and ease of use of uric acid detection are improved. First, the widths of the first and second working electrodes are obtained to clarify their direct impact on the current signal as core parameters of the effective reaction area. Then, a correction factor is generated based on the correction range to effectively reduce electrode width differences and processing errors, unifying the signal to a standard width benchmark and avoiding detection deviations caused by hardware variations. Subsequently, the total uric acid current signal and the current signal of interfering substances are corrected by combining the theoretical current signal and the correction factor. This not only accurately reduces the influence of interfering substances such as ascorbic acid but also adapts to hardware differences in electrodes of different widths. The overall operation is simple, requiring no complex procedures, and can meet the detection needs of multiple sample types such as whole blood and plasma, as well as different hardware specifications, keeping detection errors within a reasonable range and providing reliable technical support for accurate uric acid detection in various clinical scenarios.

[0098] Please see Figure 6 The sixth embodiment of a uric acid concentration detection method in this invention includes:

[0099] 601. Analyze the sensor group performance calibration data according to the preset number of days of use to obtain the sensitivity attenuation coefficient;

[0100] In this embodiment, before the sensor leaves the factory, an "initial sensitivity calibration" is performed using uric acid standard solutions of three concentrations: 100 μmol / L, 500 μmol / L, and 1000 μmol / L, and the initial sensitivity is recorded. (e.g., 2.5 μA·L / μmol·cm²); simultaneously, through accelerated aging experiments (sensitivity was periodically tested under storage conditions of 4℃, 25℃, and 37℃), the sensitivity corresponding to different usage days D (test date and production date) was obtained. This creates a calibration database of "usage days and sensitivity"; since sensor sensitivity decay follows "first-order reaction kinetics" (the decay rate decreases exponentially with time), an exponential decay model is used for fitting. In the formula, The decay constant (determined by the storage environment: when stored at 4℃) =0.002 / day), at 25℃ ( =0.005 / day), pre-stored in the control module 1 of the detection device); sensitivity attenuation coefficient Defined as the ratio of initial sensitivity to current sensitivity, it is used to "amplify" the currently detected current signal to the signal strength corresponding to the initial state, thus offsetting the attenuation effect. Example: If the sensor is used for 30 days (stored at 25℃), then... This means that the current sensitivity is only 86% of the initial value, and the correction current signal needs to be multiplied by 1.162 to restore it to the signal level without attenuation.

[0101] 602. Analyze the temperature data of the reaction electrode region according to the preset reaction time to obtain the temperature compensation coefficient;

[0102] In this embodiment, the core reaction (electrochemical oxidation) for uric acid detection is extremely sensitive to temperature: for every 1°C deviation from the standard reaction temperature (37°C), and with a longer reaction time, the impact of temperature fluctuations accumulates. An NTC temperature sensor (accuracy ±0.1°C) is embedded in the reaction electrode area to collect temperature data at a frequency of 1Hz throughout the entire reaction process (from the application of pre-voltage to current acquisition, approximately 50-60 seconds), obtaining... The average temperature over the reaction time (e.g., 55 seconds) (to avoid errors caused by instantaneous temperature fluctuations); the formula for calculating the temperature compensation coefficient is as follows:

[0103] In the formula, The standard reaction temperature, For temperature coefficient, Standard reaction time For average temperature, the model logic is: the longer the reaction time... The impact of temperature deviation is amplified, and the temperature compensation coefficient needs to be adjusted synchronously to ensure that the cumulative error is offset.

[0104] 603. Perform type analysis on the preset test samples to obtain the sample dilution factor;

[0105] In this embodiment, the sample dilution factor is the optimal dilution factor preset according to the sample type;

[0106] 604. The uric acid concentration value is obtained by analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the correction current signal, sample dilution factor, sensitivity attenuation coefficient and temperature compensation coefficient.

[0107] In this embodiment, an exponential decay model combined with accelerated aging test data is used to generate a sensitivity decay coefficient to offset the performance drift of the sensor over the number of days of use. A temperature compensation coefficient is constructed by fusing reaction time and average temperature to reduce the cumulative effect of temperature drift and adapt to a wide temperature range. Finally, the uric acid concentration value is obtained by combining the calibration current signal with multiple coefficients. This solution requires no complicated operation, is compatible with portable devices, and balances detection accuracy, environmental adaptability, and ease of use. It extends the effective life of the sensor, meets the needs of accurate detection in multiple scenarios such as clinical and home use, and provides stable and reliable technical support for uric acid detection.

[0108] Please see Figure 7 The seventh embodiment of a uric acid concentration detection method in this invention includes: 701. Determining whether the current signal of the interfering substance is less than or equal to the theoretical current signal;

[0109] 702. When the current signal of the interfering substance is less than or equal to the theoretical current signal, a correction current signal is generated based on the total uric acid current signal.

[0110] In this embodiment, the interfering substance current signal is collected by the second working electrode 5 (WE2), which is essentially the oxidation current of reducing interfering substances (ascorbic acid, dopamine, levodopa, etc.) in the blood sample under the applied voltage of WE2; the voltage strategy of WE2 is "slightly greater than the oxidation potential of ascorbic acid ( And lower than the uric acid oxidation potential ( (e.g., 0.2~0.25V), therefore only interfering substances will undergo oxidation reactions in this potential range. It directly reflects the total content of interfering substances;

[0111] 703. Conversely, the total uric acid current signal and the interfering substance current signal are corrected according to the correction factor and the theoretical current signal to obtain the corrected current signal.

[0112] In this embodiment, the correction current signal is = ,

[0113] In the formula, This represents the total uric acid current signal. To interfere with the material current signal, As a correction factor, The value is related to the width of the first working electrode 4 and the second working electrode 5, and its value ranges from 0.5 to 10, preferably from 1 to 5. The theoretical current signal is the current signal measured at room temperature when there are no interfering substances on the second working electrode 5. It is the critical threshold for distinguishing between "negligible interference" and "interference that needs to be corrected". The total uric acid current signal is collected by the first working electrode 4 (WE1) and includes the uric acid oxidation current (target signal) + a small amount of interfering current (such as the residual oxidation current of acetaminophen). The voltage strategy of WE1 is "slightly greater than the uric acid oxidation potential and lower than the acetaminophen oxidation potential" to suppress acetaminophen interference to the greatest extent. Therefore, the total uric acid current signal contains only a very small amount of non-target signal. It is necessary to combine the current signal of interfering substances to further eliminate the reducing interference.

[0114] Interference subtraction under low uric acid conditions: Example: The current signal collected by the first working electrode 4 is corrected using the current signal of the second working electrode 5. The corrected current signal of the first working electrode 4 and the interference deviation are shown in Table 5.

[0115] Table 5

[0116]

[0117] Interference subtraction under high uric acid conditions: Example: The current signal collected by the first working electrode 4 is corrected using the current signal from the second working electrode 5. The correction equation is as follows: The current signal and interference deviation of the first working electrode 4 after correction are shown in Table 6:

[0118] Table 6

[0119]

[0120] Based on the above data, it can be seen that, regardless of whether the uric acid measurement is at low or high concentration, by adding an anti-interference electrode—the second working electrode 5—and by applying a certain voltage to the second working electrode 5 and collecting the current signal, while controlling the voltage applied to the first working electrode 4, and combining it with an appropriate current signal correction equation, the interference of reducing substances such as ascorbic acid can be effectively eliminated. After the interference signal is corrected, the precision and stability of the current signal of uric acid itself are not affected, and the deviation caused by the interference substances is kept within ±10%. This shows that the technical effect of this method is very effective.

[0121] In this embodiment, the accuracy and applicability of uric acid detection are improved by addressing the influence of reducing interfering substances in blood samples. A graded correction method using the theoretical current signal as the critical threshold is employed to avoid over-correction under low interference conditions and to selectively subtract excess interference under high interference conditions. Simultaneously, a correction factor is used to reduce hardware errors caused by differences in electrode width. This solution balances anti-interference capabilities with hardware compatibility, is simple and easy to implement, adapts to portable devices, exhibits high long-term detection stability, covers complex clinical blood sample scenarios, and keeps detection errors within a reasonable range, meeting the needs of precise clinical detection.

[0122] The above describes a method for detecting uric acid concentration in an embodiment of the present invention. The following describes a device for detecting uric acid concentration in an embodiment of the present invention. Please refer to [link to relevant documentation]. Figure 8 A uric acid concentration detection device includes a control module 1 and an impedance electrode 2, a uric acid instrument 3, a first working electrode 4, a second working electrode 5, and a sensor group 6 electrically connected to the control module 1; a reaction electrode region is formed between the impedance electrode 2, the uric acid instrument 3, the first working electrode 4, the second working electrode 5, and the sensor group 6; the control module 1 is used to execute a uric acid concentration detection method as described above; the first working electrode 4 can serve as both the impedance electrode 2 and the background electrode; the conductive ink of the reference electrode is composed of silver and silver chloride, while the impedance electrode 2 and the reference electrode are made of conventional carbon ink;

[0123] The uric acid concentration detection device also includes an insulating substrate 7, on which the first working electrode 4 and the second working electrode 5 are printed; the raw materials of the first working electrode 4 and the second working electrode 5 include conductive ink, and the raw material of the impedance electrode 2 includes conventional carbon ink; the sensor group 6 includes a conductive wire layer 8, a reference electrode 9, a sampling electrode 10, a sampling channel layer 11, and a hydrophilic film layer 12 (including an exhaust hole 121).

[0124] The conductive ink is a conductive carbon ink doped with a water-soluble redox conductive medium; the first working electrode 4 and the second working electrode 5 are obtained by printing and drying, and their composition is conductive carbon powder, resin, solvent, dispersant and water-soluble redox conductive medium, with the total weight of all raw materials calculated as 100 parts by weight.

[0125] The conductive ink used for the first working electrode 4 and the second working electrode 5 is prepared by adding resin, solvent, conductive carbon powder and dispersant in 100 parts by weight, stirring and mixing, then adding water-soluble redox conductive medium, stirring and mixing again, and then grinding 3-4 times with a sampling three-roll mill to make the particle size below 10um.

[0126] The selected water-soluble redox conductive media have relatively low redox potentials, including any one of: hexaammonium trichloride, benzoquinone and its derivatives, Meldora blue and ferrocene and its derivatives;

[0127] The selected resin is chosen from one or a combination of several of the following: acrylic resin, polyurethane resin, polyamide resin, epoxy resin, phenolic resin, polyvinyl chloride resin, and polyester resin.

[0128] The selected solvent is selected from one or a combination of several of the following: ethylene glycol ethyl ether acetate, dimethyl succinate, diethylene glycol monobutyl ether, diethylene glycol butyl ether acetate, ethyl acetate, butyl acetate, propylene glycol methyl ether acetate, dimethyl adipic acid, and diethylene glycol ethyl ether acetate.

[0129] The selected dispersant is chosen from one or a combination of several of the following: octylphenol polyoxyethylene ether, sodium polyacrylate, polyvinylpyrrolidone, styrene-maleic anhydride resin, TIG, alkylphenol ethoxysulfate sodium carboxymethyl cellulose, etc.

[0130] The surface of sensor group 6 also has a layer of double-sided adhesive and a hydrophilic film layer.

[0131] Double-sided tape provides a sampling channel, and the hydrophilic membrane provides a sampling siphon function. There is an air vent at the other end of the sampling port, which facilitates the smooth aspiration of blood samples into the channel.

[0132] The electrode surface of the uric acid electrochemical sensor does not require coating, dispensing, or screen printing of anti-interference enzyme solution and conductive dielectric coating;

[0133] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the system, device, or unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0134] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0135] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for detecting uric acid concentration, characterized in that, An apparatus for detecting uric acid concentration is provided, the apparatus comprising an impedance electrode, a uric acid analyzer, a first working electrode, a second working electrode, and a sensor assembly; a reaction electrode region is formed between the impedance electrode, the uric acid analyzer, the first working electrode, the second working electrode, and the sensor assembly; the method for detecting uric acid concentration includes the following steps: Obtain the state of the reaction electrode region; The oxidation potentials of uric acid and acetaminophen were obtained based on the state of the reaction electrode region. Based on the preset first voltage application range, the preset second voltage application range, the uric acid oxidation potential and the acetaminophen oxidation potential, the first working electrode and the second working electrode are controlled to collect the total uric acid current signal and the interference substance current signal. Acquire the reaction temperature of the test sample and the output signal of the sensor group; The uric acid concentration value is obtained by analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the total uric acid current signal and the current signal of the interfering substances.

2. The method for detecting uric acid concentration as described in claim 1, characterized in that, The process of obtaining the uric acid oxidation potential and acetaminophen oxidation potential based on the state of the reaction electrode region includes: The state of the reaction electrode region was analyzed; When the state of the reaction electrode region is that the blood sample has arrived at the reaction electrode region, the impedance electrode is controlled to apply a sinusoidal AC signal to the reaction electrode region according to the preset working frequency. Under the applied sinusoidal AC signal, real-time impedance data is collected according to the preset acquisition frequency; Time-domain analysis was performed on the real-time impedance data to obtain the impedance change rate; Determine whether the rate of change of impedance is less than a preset threshold for the rate of change of impedance; When the rate of change of impedance is less than the threshold of the rate of change of impedance, the uric acid oxidation potential and the acetaminophen oxidation potential are obtained.

3. The method for detecting uric acid concentration as described in claim 1, characterized in that, The process of controlling the first and second working electrodes to acquire the total uric acid current signal and the interfering substance current signal according to the preset first voltage application range, the preset second voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential includes: A first voltage application strategy is generated based on the first voltage application range, the uric acid oxidation potential, and the acetaminophen oxidation potential. The uric acid instrument is controlled to apply a pre-voltage to the first working electrode according to the first voltage application strategy; Obtain the oxidation potential of ascorbic acid; The second voltage application strategy is generated based on the second voltage application range, the first voltage application strategy, the uric acid oxidation potential, and the ascorbic acid oxidation potential. The uric acid instrument is controlled to apply a decreasing voltage to the second working electrode according to the second voltage application strategy; The pre-voltage application state is acquired, and the pre-voltage application state is analyzed according to a preset first application duration threshold. When the pre-voltage application state reaches the first application duration threshold, the falling voltage application state is obtained, and the falling voltage application state is analyzed according to the preset second application duration threshold. When the applied voltage reaches the second application duration threshold, the first and second working electrodes are controlled to acquire the total uric acid current signal and the interfering substance current signal according to the preset acquisition frequency.

4. The method for detecting uric acid concentration as described in claim 1, characterized in that, The step involves analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the total uric acid current signal and the current signal of interfering substances to obtain the uric acid concentration value, including: The total uric acid current signal and the interfering substance current signal are corrected according to the preset correction range to obtain the corrected current signal; Acquire sensor group performance calibration data and reaction electrode area temperature data; The uric acid concentration value is obtained by analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the calibration current signal, sensor group performance calibration data and reaction electrode area temperature data.

5. The method for detecting uric acid concentration as described in claim 4, characterized in that, The step of correcting the total uric acid current signal and the interfering substance current signal according to a preset correction range to obtain a corrected current signal includes: The width of the first working electrode and the width of the second working electrode are obtained to obtain the width of the first working electrode and the width of the second working electrode. A correction factor is generated based on the correction range, the width of the first working electrode, and the width of the second working electrode. The total uric acid current signal and the current signal of interfering substances are corrected according to the preset theoretical current signal and correction factor to obtain the corrected current signal.

6. The method for detecting uric acid concentration as described in claim 4, characterized in that, The step involves analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the calibration current signal, sensor group performance calibration data, and reaction electrode area temperature data to obtain the uric acid concentration value, including: The sensor group performance calibration data are analyzed based on the preset number of days of use to obtain the sensitivity attenuation coefficient; The temperature data of the reaction electrode region is analyzed according to the preset reaction time to obtain the temperature compensation coefficient. Perform type analysis on the preset test samples to obtain the sample dilution factor; The uric acid concentration value is obtained by analyzing the reaction temperature of the test sample and the output signal of the sensor group based on the correction current signal, sample dilution factor, sensitivity attenuation coefficient and temperature compensation coefficient.

7. The method for detecting uric acid concentration as described in claim 5, characterized in that, The step of correcting the total uric acid current signal and the interfering substance current signal according to a preset theoretical current signal and correction factor to obtain a corrected current signal includes: Determine whether the current signal of the interfering substance is less than or equal to the theoretical current signal; When the current signal of the interfering substance is less than or equal to the theoretical current signal, a correction current signal is generated based on the total uric acid current signal. Conversely, the total uric acid current signal and the interfering substance current signal are corrected according to the correction factor and the theoretical current signal to obtain the corrected current signal.

8. A uric acid concentration detection device, characterized in that, The device includes a control module and an impedance electrode, a uric acid analyzer, a first working electrode, a second working electrode, and a sensor group electrically connected to the control module; a reaction electrode region is formed between the impedance electrode, the uric acid analyzer, the first working electrode, the second working electrode, and the sensor group; the control module is used to perform a uric acid concentration detection method as described in any one of claims 1-7.

9. The uric acid concentration detection device as described in claim 8, characterized in that, The uric acid concentration detection device also includes an insulating substrate, on which the first working electrode and the second working electrode are printed; the raw materials of the first working electrode and the second working electrode include conductive ink, and the raw material of the impedance electrode includes conventional carbon ink.

10. The uric acid concentration detection device as described in claim 9, characterized in that, The conductive ink is a conductive carbon ink doped with a water-soluble redox conductive medium.

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