Hematocrit correction method applied to uric acid tester

Abstract

The invention discloses a hematocrit correction method applied to a uric acid tester. The method specifically comprises the following steps: step 1, acquiring a vein whole blood sample after uric acid concentration is adjusted; 2, adjusting the hematocrit of each blood sample to be 20%, 30%, 40%, 50%, 60% and 70% respectively based on the vein whole blood sample in the step 1; 3, setting an inspection standard; and 4, correcting the hematocrit of the blood sample adjusted in the step 2 based on the inspection standard in the step 3 to realize the hematocrit correction based on the application of the uric acid tester. The invention is used for solving the HCTlt of the portable uric acid tester; when the volume of pressure is larger than 35% or larger than 55%, the portable uric acid tester is large in deviation and poor in accuracy.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biotechnology, and particularly relates to a hematocrit correction method applied to a uric acid tester. BACKGROUND

[0002] The uric acid tester is a portable uric acid detection device, which is used for collecting capillary blood and performing rapid detection by using a rapid blood uric acid test paper, and is particularly suitable for hyperuricemia patients who need to frequently detect uric acid. However, the hematocrit (HCT) of the patient has a great influence on the detection result of the portable uric acid tester. Hospital collects anticoagulated venous blood samples, takes venous blood supernatant, and detects the uric acid level by using a biochemical analyzer. Studies have shown that when HCT is less than 35% or greater than 55%, the portable uric acid tester has a large deviation and poor accuracy. SUMMARY

[0003] The application provides a hematocrit correction method applied to a uric acid tester, which is used to solve the problem that when HCT of the portable uric acid tester is less than 35% or greater than 55%, the portable uric acid tester has a large deviation and poor accuracy.

[0004] The application is achieved by the following technical scheme: A hematocrit correction method applied to a uric acid tester, the hematocrit correction method comprising the following steps: Step 1: obtaining a venous whole blood sample with adjusted uric acid concentration; Step 2: adjusting the hematocrit of each blood sample to be 20%, 30%, 40%, 50%, 60% and 70% respectively based on the venous whole blood sample in step 1; Step 3: setting a test standard; Step 4: correcting the hematocrit of the blood sample adjusted in step 2 based on the test standard in step 3, so as to realize hematocrit correction based on the uric acid tester.

[0005] Further, the step 1 specifically adjusts the uric acid concentration so that the uric acid test range is distributed between 174 and 1190 μmol / L.

[0006] Further, the step 3 specifically comprises Step 3.1: testing different Hct samples based on the venous whole blood sample adjusted in step 2; Step 3.2: calculating the deviation of the mean value based on the test result in step 3.1, and setting a test standard.

[0007] Further, the step 3.1 specifically comprises the following steps: Step 3.1.1 Before each test, the blood sample should be gently inverted to mix it evenly; Step 3.1.2 Divide the venous whole blood sample 1 with Hct of 20% into two parts, centrifuge the first part at high speed, and use a biochemical analyzer to perform one test; Step 3.1.3 Test the second part using a uric acid tester and uric acid test paper, test 10 times for each uric acid tester, and record the test values; Step 3.1.4 Repeat steps 3.1.2-3.1.3 to complete the testing of other different Hct samples of venous whole blood sample 1, and record the test values; Step 3.1.5 Repeat steps 3.1.2-3.1.4 to complete the testing of other venous whole blood samples.

[0008] Further, the step 3.2 specifically calculates the deviation of the average test value of each venous whole blood sample with different Hct samples from the average test value of the 42% Hct sample; the relative deviation of the average test value of each venous whole blood sample with different Hct samples from the average test value of the 42% Hct sample should not exceed ±10%.

[0009] Further, the step 5 includes the following steps: Step 5.1: Obtain the current value and impedance value corresponding to the test paper test; Step 5.2: Based on the values obtained in step 5.1, perform linear assignment; Step 5.3: Based on the linear assignment of step 5.2, obtain the hematocrit correction formula; Step 5.4: Based on the hematocrit correction formula of step 5.3, obtain the low value high hematocrit formula; Step 5.5: Based on the low value high hematocrit formula of step 5.4, implement segmented hematocrit correction for each blood sample; Step 5.6: Perform segmented hematocrit correction on step 5.3; verify the uric acid test paper hematocrit correction algorithm.

[0010] Further, the step 5.1 specifically uses the uric acid test paper as a model, and when testing a uric acid sample, the original data of the test is derived through the uric acid tester to obtain the current value and impedance value corresponding to the test paper test.

[0011] Further, the step 5.2 specifically prepares multiple uric acid samples with different concentrations, so that the hematocrit is 42%, and the current value corresponding to each sample is obtained using the uric acid tester; take the current value of the 42% hematocrit sample, and use the test value of the comparison instrument as the target value to assign the uric acid value to the current value of the 42% hematocrit sample; take the current value as the X axis and the target value as the Y axis to obtain the linear formula: y = -131.02024407 x 2 + 1,369.80127010 x - 133.81316120 (1).

[0012] Further, the step 5.3 is specifically taking the samples of multiple low hematocrit segments to compensate the packed cell volume correction formula, and obtaining the average current value and the average impedance value through the sample testing of the uric acid instrument; The step 5.4 is specifically dividing the current value of each packed cell sample in each sample by the 42% packed cell current value of the same sample to obtain the current ratio value; Taking the average impedance value as the X axis and the current ratio value as the Y axis, a polynomial linear formula is obtained, that is, the packed cell volume correction formula: y = -0.00657092 x 2 + 0.20520706 x + 0.05788101 (2).

[0013] Further, the step 5.5 is specifically dividing the current value*1000 by the corresponding impedance value to obtain the current / impedance coefficient, and obtaining the current / impedance coefficient range corresponding to the low concentration and high packed cell volume, and setting the low value and high packed cell volume judgment condition in the instrument algorithm, when the current / impedance coefficient>25.0, the impedance correction formula (1) is taken; When the current / impedance coefficient≤25.0, the impedance correction formula (2) is taken: After the judgment is completed, the formula is substituted into the calculation to obtain the current ratio value, and the corrected current value can be obtained; At this time, the corrected current value obtained by the correction is the current correction value corresponding to 42% packed cell volume; The current value corresponding to 42% packed cell volume or the current correction is substituted into the linear formula to obtain the theoretical uric acid value, and then the uric acid values at different packed cell volumes are compared with the uric acid value at 42% packed cell volume; The step 5.6 is specifically, When the uric acid concentration is 174-297 μmol / L, 477-595 μmol / L or 893-1190 μmol / L, the segmented packed cell volume correction method can cover the packed cell volume range of 20%-70%, and the deviation compared with 42% packed cell volume is within ±10%.

[0014] The beneficial effects of the present application are: The present application covers the samples with 20%-70% packed cell volume, and the test accuracy is high. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 It is the method flowchart of the present application. DETAILED DESCRIPTION

[0016] In the following description, for purposes of explanation and not limitation, specific details are set forth such as particular architectures, technologies, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

[0017] It is to be understood that the terminology "including", when used in the present specification and in the following claims, indicates the presence of the stated features, integers, steps, operations, elements, and / or components but does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0018] It is also to be understood that the terminology used in the present specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the present application. As used in this specification and the appended claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0019] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, it will be apparent to one skilled in the art that the present application can be practiced without the specific details presented herein. In other instances, well-known methods have not been described in detail in order to avoid obscuring the present application. Embodiments

[0020] A hematocrit correction method applied to a uric acid tester, the hematocrit correction method comprising the following steps: Step 1: Obtain a venous whole blood sample after adjusting the uric acid concentration; Step 2: Based on the venous whole blood sample of step 1, adjust the hematocrit of each blood sample to be: 20%, 30%, 40%, 50%, 60%, and 70%, respectively; Step 3: Set a test standard; Step 4: Correct the hematocrit of the blood sample adjusted in step 2 based on the test standard of step 3, to realize the hematocrit correction based on the uric acid tester application.

[0021] Step 1, prepare a venous whole blood sample, adjust the uric acid concentration in the venous whole blood sample, so that the uric acid test range is distributed between 174 and 1190 μmol / L.

[0022] Step 2, adjust the hematocrit of each blood sample, so that the hematocrit of each venous whole blood sample with different uric acid concentration is: 20%, 30%, 40%, 50%, 60%, and 70%, respectively.

[0023] Preparation of Hct from the blood sample to be tested

[0024] Step 3.1, Preparation method: Step 3.1.1 Before each test, the blood sample should be gently inverted to ensure it is thoroughly mixed; Step 3.1.2 Divide the venous whole blood sample with Hct of 20% into two parts. Centrifuge the first part at high speed and perform one test using a biochemical analyzer. Step 3.1.3 The second test was conducted using a uric acid analyzer and uric acid test strips. Each uric acid analyzer was used to perform 10 tests, and the test values ​​were recorded. Step 3.1.4 Repeat steps 3.1.2 to 3.1.3 to complete the testing of other different Hct samples of venous whole blood sample 1 and record the test values; Step 3.1.5 Repeat steps 3.1.2 to 3.1.4 to complete the testing of other venous whole blood samples.

[0025] Step 3.2, Standard: Calculate the deviation of the mean test value of different Hct samples from each venous whole blood sample relative to the mean test value of the 42% Hct sample. The relative deviation of the mean test value of different Hct samples from each venous whole blood sample relative to the mean test value of the 42% Hct sample should not exceed ±10%.

[0026] Step 4: Hematocrit Correction Step 4.1 Using uric acid test strips as a model, when testing uric acid samples, export the raw test data through the uric acid analyzer to obtain the corresponding current and impedance values ​​during the test strip test. See the table below:

[0027]

[0028]

[0029]

[0030]

[0031] Step 4.2 Linear assignment of uric acid: Since 42% hematocrit is the median value for most people, it was used as the calibration median. Multiple uric acid samples of different concentrations were prepared to ensure that the hematocrit of each erythrocyte was 42%, and the current value corresponding to each sample was obtained using a uric acid analyzer.

[0032] The current value of a 42% cytotoxicity sample was used as the target value, and the uric acid value was assigned to the current value of the 42% cytotoxicity sample. With the current value on the X-axis and the target value on the Y-axis, the linear formula was derived as follows: y = -131.02024407x2 + 1,369.80127010x - 133.81316120.

[0033]

[0034] Step 4.3 Calculate the hematocrit correction formula: Obtain the mean current ① and mean impedance ② using a uric acid analyzer; divide the current value of each hematocrit sample in each sample by the 42% hematocrit current value of the same sample to obtain the current ratio ③. Using the mean impedance ② as the X-axis and the current ratio ③ as the Y-axis, obtain a polynomial linear formula, which is the hematocrit correction formula 1. Hematocrit formula 1 is: y = -0.00548048 x² + 0.20550551x + 0.02009601. Substitute the formula into the formula for verification to obtain the current ratio ④. ④ * ① gives the corrected current value. The corrected current value is now the current correction value corresponding to the 42% hematocrit ⑤. Substitute ⑤ into the linear formula to obtain the theoretical uric acid value ⑥. Then, the theoretical uric acid value of each sample was compared with the 42% hematocrit. It was found that the correction value of uric acid samples with low concentration high hematocrit (hematocrit range of 60%~70%) deviated from the ±10% range, which was a large deviation. The low-value high hematocrit formula was derived from multiple HCT samples with low uric acid concentration values, namely HCT correction formula 2, and segmented hematocrit correction was performed.

[0035]

[0036]

[0037]

[0038]

[0039]

[0040] Step 4.4 Derivation of the Low-Value High-Pressure Product Formula Multiple samples from low-value ranges were used for hematocrit correction. The mean current (①) and mean impedance (②) were obtained by testing the samples with a uric acid instrument. The current value of each hematocrit sample in each sample was divided by 42% of the hematocrit current value of the same sample to obtain the current ratio (③). Using the mean impedance (②) as the X-axis and the current ratio (③) as the Y-axis, a polynomial linear formula was obtained, which is the hematocrit correction formula 2. The hematocrit formula 2 is: y = -0.00657092 x² + 0.20520706 x + 0.05788101.

[0041]

[0042]

[0043]

[0044] Step 4.5 Segmented cumulus correction: Multiply the current value by 1000 and divide by the corresponding impedance value to obtain the current / impedance coefficient (⑧). This gives the range of current / impedance coefficients corresponding to the low-concentration high-pressure product. Set the low-value high-pressure product judgment condition in the instrument algorithm. When the current / impedance coefficient > 25.0, use impedance correction formula 1: y = -0.00548048 x² + 0.20550551x + 0.02009601. When the current / impedance coefficient ≤ 25.0, use impedance correction formula 2: y = -0.00657092 x² + 0.20520706 x + 0.05788101. After judgment, substitute the formulas into the calculation to obtain the current ratio (④ or ⑨). ④ * ① or ⑨ * ① will give the corrected current value. At this point, the corrected current value is the current correction value (⑤ or ⑩) corresponding to the 42% product. Substitute ⑤ or ⑩ into the linear formula to obtain the theoretical uric acid value, and then compare the uric acid values ​​of different calorimeters with the uric acid value of 42% calorimeter.

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053]

[0054]

[0055] Step 4.6 Verification of the uric acid test strip hematocrit correction algorithm: Concentration 1

[0056] Concentration 2

[0057] Concentration 3

[0058] The above verification data shows that within the uric acid range of 174~1190μmol / L, this segmented hematocrit correction method can cover 20%~70% of the hematocrit range, and the deviation compared to the 42% hematocrit is within ±10%.

[0059] Technical advantages: This segmented correction algorithm can significantly improve the sample hematocrit range of the test strip, accurately testing 20% ​​to 70% of the hematocrit. This indicates that the hematocrit correction method used in the uric acid detector of this application has higher accuracy and can quickly and accurately test uric acid in the blood.

[0060] Uric acid can be replaced with blood sugar and cholesterol, and the methodology for hematocrit correction is consistent.

Claims

1. A hematocrit correction method for a uric acid tester application, characterized by, The hematocrit correction method comprises the following steps: Step 1: Obtain the adjusted uric acid concentration of the venous whole blood sample; Step 2: Based on the venous whole blood sample of step 1, adjust the hematocrit of each blood sample to be 20%, 30%, 40%, 50%, 60%, and 70%, respectively; Step 3: Set the test standard; Step 4: Correct the hematocrit of the blood sample adjusted in step 2 based on the test standard of step 3, and realize the hematocrit correction based on the uric acid tester application.

2. The hematocrit correction method according to claim 1, characterized by, The step 1 is specifically adjusting the uric acid concentration to distribute the uric acid test range between 174 and 1190 μmol / L.

3. The hematocrit correction method according to claim 1, characterized by, The step 3 specifically includes Step 3.1: Test different Hct samples on the venous whole blood sample adjusted in step 2; Step 3.2: Calculate the deviation of the mean value based on the test results of step 3.1, and set the test standard.

4. The hematocrit correction method according to claim 3, characterized by, The step 3.1 specifically includes the following steps: Step 3.1.1 Before each test, the blood sample should be gently inverted to mix evenly; Step 3.1.2 Divide the venous whole blood sample 1 with Hct of 20% into two parts, centrifuge the first part at high speed, and use a biochemical analyzer to test once; Step 3.1.3 Test the second part using a uric acid tester and uric acid test paper, test 10 times for each uric acid tester, and record the test values; Step 3.1.4 Repeat steps 3.1.2-3.1.3 to complete the test of other different Hct samples of venous whole blood sample 1, and record the test values; Step 3.1.5 Repeat steps 3.1.2-3.1.4 to complete the test of other venous whole blood samples.

5. The hematocrit correction method according to claim 4, characterized in that, The step 3.2 is specifically calculating the deviation of the mean value of the test values of different Hct samples of each venous whole blood sample relative to the mean value of the test values of 42% Hct sample; the relative deviation of the mean value of the test values of different Hct samples of each venous whole blood sample relative to the mean value of the test values of 42% Hct sample should not exceed ±10%.

6. The hematocrit correction method of claim 1, wherein, The step 4 includes the following steps: Step 4.1: Obtain the current value and impedance value corresponding to the test paper test; Step 4.2: Based on the values obtained in step 4.1, perform linear assignment; Step 4.3: Based on the linear assignment of step 4.2, obtain the hematocrit correction formula; Step 4.4: Based on the hematocrit correction formula of step 4.3, obtain the low value high hematocrit formula; Step 4.5: Based on the low value high hematocrit formula of step 4.4, realize segmented hematocrit correction for the hematocrit of each blood sample; Step 4.6: Verify the uric acid test paper hematocrit correction algorithm based on the segmented hematocrit correction of step 4.

3.

7. The hematocrit correction method according to claim 6, characterized in that, The step 4.1 is specifically using uric acid test paper as a model, testing uric acid samples, and exporting the original data of the test through the uric acid tester to obtain the current value and impedance value corresponding to the test paper test.

8. The hematocrit correction method according to claim 6, characterized by, The step 4.2 is specifically that: a plurality of different concentrations of uric acid samples are prepared, the hematocrit is 42%, the current value corresponding to each sample is obtained by using a uric acid tester; the current value of the sample with 42% hematocrit is taken, the test value of the comparison instrument is taken as a target value, and the current value of the sample with 42% hematocrit is assigned a uric acid value; the linear formula is obtained by taking the current value as the X axis and the target value as the Y axis: y = -131.02024407 x 2 + 1,369.80127010 x - 133.81316120 (1).

9. The hematocrit correction method according to claim 6, wherein, The step 4.3 is specifically that: the samples in a plurality of low-value sections are taken for hematocrit correction formula compensation, and the current mean value and the impedance mean value are obtained by testing the samples by using a uric acid instrument; The step 4.4 is specifically that: the current value of each hematocrit sample in each sample is divided by the current value of the sample with 42% hematocrit, and the current ratio is obtained; The polynomial linear formula is obtained by taking the impedance mean value as the X axis and the current ratio as the Y axis, that is, the hematocrit correction formula: y = -0.00657092 x 2 + 0.20520706 x + 0.05788101 (2).

10. The hematocrit correction method according to claim 9, characterized by, The step 4.5 is specifically that: the current value is multiplied by 1000, then divided by the corresponding impedance value, the current / impedance coefficient is obtained, the current / impedance coefficient range corresponding to low concentration and high hematocrit is obtained, and the low-value high-hematocrit judgment condition is set in the instrument algorithm; when the current / impedance coefficient is greater than 25.0, the impedance correction formula (1) is taken; When the current / impedance coefficient is less than or equal to 25.0, the impedance correction formula (2) is taken: After the judgment is completed, the formula is substituted into the check, the current ratio is obtained, and the corrected current value is obtained; At this time, the current value corrected by the correction is the current correction value corresponding to 42% hematocrit; The theoretical uric acid value is obtained by substituting the current value corresponding to 42% hematocrit or the current correction into the linear formula, and then the uric acid values at different hematocrits are compared with the uric acid value at 42% hematocrit; The step 4.6 is specifically that: When the uric acid concentration is 174-297 μmol / L, 477-595 μmol / L or 893-1190 μmol / L, the segmented hematocrit correction method can cover a hematocrit range of 20%-70%, and the deviation compared with 42% hematocrit is within ±10%.

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