Method and device for measuring hematocrit

Abstract

The invention relates to a hematocrit measurement method and device, and the method comprises the steps: applying an AC signal with a preset frequency to a to-be-measured blood sample, obtaining an impedance real part and an impedance imaginary part of the to-be-measured blood sample, substituting the ratio of the impedance real part to the impedance imaginary part into a preset linear equation, and obtaining the hematocrit of the to-be-measured blood, the method comprises the following steps: respectively applying alternating current signals with a preset frequency to a plurality of blood samples with different concentrations and different hematocrites to obtain impedances and phase angles of the plurality of blood samples under the preset frequency, and obtaining a ratio of an impedance real part to an impedance imaginary part of the plurality of blood samples under the preset frequency according to the impedances and phase angles of the plurality of blood samples under the preset frequency; according to the method, linear fitting is carried out on the ratio of the impedance real part to the impedance imaginary part of the plurality of blood samples under the preset frequency and the corresponding hematocrit, so that the linear correlation coefficient of the fitted linear equation can be effectively improved, and the measurement accuracy of the hematocrit can be effectively improved.

Description

Technical Field

[0001] The present application belongs to the field of electrochemical biosensor technology, and in particular, relates to a method and device for measuring hematocrit. Background Art

[0002] Hematocrit is an important parameter for characterizing blood samples in medical testing and is an important auxiliary judgment data in the measurement and utilization of blood viscosity.

[0003] At present, the conventional method for measuring hematocrit is generally to adopt impedance measurement method, in which the blood glucose meter applies alternating current signals of different frequencies to the test strip, tests the impedance of the hematocrit at different frequencies, linearly fits the impedance and the hematocrit to obtain a linear equation of impedance and hematocrit, substitutes the impedance of the blood to be tested into the linear equation of impedance and hematocrit to measure the hematocrit, because the impedance value of the test strip electrode is large and the consistency is poor, especially the carbon electrode test strip prepared by carbon slurry, the impedance precision of the test is poor, which leads to the low linear correlation coefficient of the fitted linear equation, resulting in low accuracy of the measured hematocrit.

[0004] Therefore, how to improve the measurement accuracy of hematocrit is a technical problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0005] The purpose of the present application is to provide a method and device for measuring hematocrit; the method and device for measuring hematocrit provided in the present application can effectively improve the linear correlation coefficient of the fitted linear equation, thereby effectively improving the measurement accuracy of hematocrit.

[0006] The technical solutions provided by this application are as follows: A method for measuring hematocrit, comprising: Applying an alternating current signal of a preset frequency to the blood sample to be tested; Obtaining the real impedance part and the imaginary impedance part of the blood sample to be tested; Substituting the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; Wherein, the preset linear equation is obtained by the following method: Applying an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedance and phase angle of the plurality of blood samples at the preset frequency; Obtaining a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at a preset frequency according to the impedance and phase angle of the plurality of blood samples at a preset frequency; The ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the preset frequency is linearly fitted with the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency.

[0007] Optionally, the preset frequency is determined by the following method: Applying an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedances and phase angles of the plurality of blood samples at the initial frequency; Obtaining a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at the initial frequency according to the impedance and phase angle of the plurality of blood samples at the initial frequency; Performing a linear fit on the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the initial frequency and the corresponding pressure product to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; According to the initial linear equation at the initial frequency, a linear correlation coefficient of the initial linear equation at the initial frequency is obtained; Determining whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; If yes, the initial frequency is used as the preset frequency; If not, the frequency is adjusted and the above steps are repeated until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and the adjusted frequency is used as the preset frequency.

[0008] Optionally, the preset frequency is preferably 200KHZ.

[0009] Optionally, the initial frequency ranges from 100KHZ to 200KHZ.

[0010] Optionally, the alternating current signal is a sinusoidal alternating current signal.

[0011] The present application also provides a device for measuring hematocrit, comprising: An application module, used for applying an alternating current signal of a preset frequency to the blood sample to be tested; A first acquisition module is used to acquire the real impedance part and the imaginary impedance part of the blood sample to be tested; A first processing module, used for substituting the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; A second acquisition module, used to apply an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to acquire impedance and phase angle of the plurality of blood samples at the preset frequency; A second processing module, configured to obtain a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at a preset frequency according to the impedance and phase angle of the plurality of blood samples at a preset frequency; The third processing module is used to perform linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at a preset frequency and the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency.

[0012] Optionally, the device further comprises: A third acquisition module is used to apply an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to acquire impedance and phase angle of the plurality of blood samples at the initial frequency; a fourth processing module, configured to obtain a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at the initial frequency according to the impedance and phase angle of the plurality of blood samples at the initial frequency; a fifth processing module, configured to perform linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the initial frequency and the corresponding pressure product, to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; A sixth processing module, configured to obtain a linear correlation coefficient of the initial linear equation at the initial frequency according to the initial linear equation at the initial frequency; A judgment module, used to judge whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; a seventh processing module, configured to use the initial frequency as the preset frequency if the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; The eighth processing module is used to adjust the frequency if the linear correlation coefficient of the linear equation at the initial frequency is less than a preset threshold, until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and use the adjusted frequency as the preset frequency.

[0013] Optionally, the preset frequency is preferably 200KHZ.

[0014] Optionally, the initial frequency ranges from 100KHZ to 200KHZ.

[0015] Optionally, the alternating current signal is a sinusoidal alternating current signal.

[0016] Compared with the prior art, the present application provides a method and device for measuring hematocrit, which obtains the real part and imaginary part of the impedance of the blood sample to be tested by applying an alternating current signal of a preset frequency to the blood sample to be tested, and substitutes the ratio of the real part and the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested, wherein the preset linear equation is obtained by the following method: applying an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different hematocrits, respectively, to obtain the impedance and phase angle of the plurality of blood samples at the preset frequency, and obtaining the impedance and phase angle of the plurality of blood samples at the preset frequency according to the ratio of the real part and the imaginary part of the impedance. Impedance and phase angle, obtain the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at a preset frequency, linearly fit the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at the preset frequency with the corresponding pressure product, and obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency. In the present application, by linearly fitting the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at the preset frequency with the corresponding pressure product, the linear correlation coefficient of the fitted linear equation can be effectively improved, thereby effectively improving the measurement accuracy of the hematocrit. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of a process for measuring hematocrit disclosed in an embodiment of the present application; Figure 2 This is a schematic diagram of the structure of a hematocrit measuring device disclosed in an embodiment of the present application. DETAILED DESCRIPTION

[0019] In order to enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0020] It should be noted that when an element is referred to as being "fixed on" or "set on" another element, it can be directly on the other element or indirectly set on the other element; when an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0021] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0022] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0023] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the effects and purposes that can be achieved by this application.

[0024] like Figure 1 As shown, the embodiment of the present application provides a method for measuring hematocrit, comprising: S11, applying an alternating current signal of a preset frequency to the blood sample to be tested; In this embodiment, a blood glucose meter, a matching test strip and a blood glucose testing system are used as testing equipment. The preset frequency is a pre-set frequency. Specifically, the preset frequency is preferably 200KHZ, and an alternating current signal with a frequency of 200KHZ can be applied to the blood sample to be tested on the test strip.

[0025] S12, obtaining the real impedance part and the imaginary impedance part of the blood sample to be tested; In this embodiment, the impedance and phase angle of the blood sample to be tested at a preset frequency can be first collected by the sensor in the testing device, and then the real part and imaginary part of the impedance of the blood sample to be tested can be calculated based on the impedance and phase angle of the blood sample to be tested.

[0026] S13, substituting the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; In this embodiment, the preset linear equation is a pre-set linear equation, which is an equation of the ratio of the real part of the impedance to the imaginary part of the impedance at a preset frequency and the hematocrit. The ratio of the real part of the impedance to the imaginary part of the impedance of the blood sample to be tested at the preset frequency is substituted into the preset linear equation for calculation, and the hematocrit of the blood to be tested can be obtained.

[0027] The preset linear equation is obtained by the following method: S14, applying an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedances and phase angles of the plurality of blood samples at the preset frequency; In this embodiment, multiple blood samples with different concentrations and different pressure volumes can be prepared, and alternating current signals with a frequency of 200KHZ can be applied to the multiple blood samples with different concentrations and different pressure volumes on different test strips, respectively, to obtain the impedance and phase angle of the multiple blood samples at a frequency of 200KHZ collected by the sensor in the test equipment.

[0028] Specifically, five concentrations (S1-S5) can be prepared, with 7 packed volumes (10-70%) for each concentration, for a total of 35 blood samples: Concentration range: 1.4-30.6mmol / L; pressure range: 10%-70%; S1-10%, S1-20%, S1-30%, S1-40%, S1-50%, S1-60%, S1-70%; S2-10%, S2-20%, S2-30%, S2-40%, S2-50%, S2-60%, S2-70%; S3-10%, S3-20%, S3-30%, S3-40%, S3-50%, S3-60%, S3-70%; S4-10%, S4-20%, S4-30%, S4-40%, S4-50%, S4-60%, S4-70%; S5-10%, S5-20%, S5-30%, S5-40%, S5-50%, S5-60%, S5-70%; An alternating current signal with a frequency of 200 kHz is applied to 35 blood samples of different concentrations and pressure volumes on 35 test strips, and the impedance Z and phase angle P of the 35 blood samples at a frequency of 200 kHz are collected by the sensor in the test equipment.

[0029] S15, obtaining a ratio of a real impedance part to an imaginary impedance part of the multiple blood samples at the preset frequency according to the impedance and phase angle of the multiple blood samples at the preset frequency; In this embodiment, the real part of impedance and the imaginary part of impedance of each of the multiple blood samples can be calculated according to the impedance and phase angle of each of the multiple blood samples at the preset frequency, and then according to the real part of impedance and the imaginary part of impedance of each of the multiple blood samples at the preset frequency, the ratio of the real part of impedance to the imaginary part of impedance of each of the multiple blood samples at the preset frequency can be obtained.

[0030] Specifically, the real impedance part R and the imaginary impedance part X of each of the 35 blood samples can be calculated according to the impedance Z and the phase angle P of each of the 35 blood samples at a frequency of 200 kHz, and then the ratio R / X of the real impedance part R and the imaginary impedance part X of each of the 35 blood samples at a frequency of 200 kHz can be obtained according to the real impedance part R and the imaginary impedance part X of each of the 35 blood samples at a frequency of 200 kHz.

[0031] S16. Linearly fit the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at a preset frequency with the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance at the preset frequency and the pressure product.

[0032] In this embodiment, specifically, the ratio R / X of the real impedance R and the imaginary impedance X of 35 blood samples at a frequency of 200KHZ is linearly fitted with the corresponding pressure product to obtain a preset linear equation of the ratio R / X of the real impedance R and the imaginary impedance X at a frequency of 200KHZ and the pressure product. The linear equation of R / X and the pressure product is specifically: y=0.064x+0.9505; Among them, y is the compressed product and x is R / X.

[0033] In addition, the impedance Z of 35 blood samples at a frequency of 200KHZ can be linearly fitted with the corresponding pressure product to obtain a preset linear equation of the impedance Z and the pressure product at a frequency of 200KHZ. The linear equation of Z and the pressure product is specifically: y=0.0001x-0.726, Among them, y is the compressed product and x is Z.

[0034] By calculating the linear correlation coefficients of the linear equation of R / X and the compressed product and the linear equation of Z and the compressed product, it is found that the linear correlation coefficient of the linear equation of R / X and the compressed product is as high as 0.9937, while the linear correlation coefficient of the linear equation of Z and the compressed product is only 0.8949. Therefore, it can be seen that by performing linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at a preset frequency and the corresponding pressure product, the linear correlation coefficient of the fitted linear equation can be effectively improved.

[0035] In addition, the impedance value Z and the ratio of the real part of the impedance to the imaginary part of the impedance R / X obtained after the 35 blood samples were tested were substituted into the linear equation of Z and the pressure volume and the linear equation of R / X and the pressure volume, respectively, and the pressure volume calculated value of each of the 35 samples was calculated. Then, the deviation was calculated based on the pressure volume calculated value and the actual pressure volume value of the sample (i.e., the actual HCT), and the results are shown in Table 1 below:

[0036] Wherein, the deviation Z represents the impedance value Z obtained after testing each of the 35 blood samples, which is substituted into the linear equation of Z and the volume, and the deviation between the calculated volume value of each sample and the actual volume value (i.e., the actual HCT) is calculated; the deviation R / X represents the ratio R / X of the real part of the impedance and the imaginary part of the impedance obtained after testing each of the 35 blood samples, which is substituted into the linear equation of R / X and the volume, and the deviation between the calculated volume value of each sample and the actual volume value (i.e., the actual HCT) is calculated; According to the data in Table 1 above, the same test equipment is used, the same high-frequency signal input is used to test the same multiple samples, and the linear equation of the ratio R / X of the real part R and the imaginary part X of the impedance is used to fit the product HCT. Compared with the linear equation fitted by the impedance Z and the product HCT, the deviation between the HCT values ​​calculated by the two and the actual HCT value is undoubtedly smaller than that calculated by the linear equation fitting R / X and the product HCT. The deviation can be reduced by 9.90% at the lowest and 123.17% at the highest. This proves that the method of fitting a linear equation of the ratio R / X of the real part R and the imaginary part X of the impedance and the product HCT used in the present application is more accurate in measuring the product HCT of the sample to be tested, and the accuracy is far higher than the conventional impedance measurement method.

[0037] In this embodiment, steps S14 to S16 may be performed before step S13 or before step S11.

[0038] Compared with the prior art, the present application provides a method for measuring hematocrit, which obtains the real part and imaginary part of the impedance of the blood sample to be tested by applying an alternating current signal of a preset frequency to the blood sample to be tested, and substitutes the ratio of the real part and the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested, wherein the preset linear equation is obtained by the following method: applying an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different hematocrits, respectively, to obtain the impedance and phase angle of the plurality of blood samples at the preset frequency, and obtaining the impedance and phase angle of the plurality of blood samples at the preset frequency according to the impedance of the plurality of blood samples at the preset frequency. The impedance and phase angle are obtained to obtain the ratio of the real part of the impedance to the imaginary part of the impedance of multiple blood samples at a preset frequency, and the ratio of the real part of the impedance to the imaginary part of the impedance of multiple blood samples at the preset frequency is linearly fitted with the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of the impedance to the imaginary part of the impedance at the preset frequency and the pressure product. In the present application, by linearly fitting the ratio of the real part of the impedance to the imaginary part of the impedance of multiple blood samples at the preset frequency with the corresponding pressure product, the linear correlation coefficient of the fitted linear equation can be effectively improved, thereby effectively improving the measurement accuracy of the hematocrit.

[0039] As an implementation manner, in the embodiment of the present application, the preset frequency is determined by the following method: S21, applying an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedances and phase angles of the plurality of blood samples at the initial frequency; In this embodiment, an alternating current signal of an initial frequency is applied to multiple blood samples of different concentrations and different pressure volumes on different test strips, and the impedance and phase angle of the multiple blood samples at the initial frequency collected by the sensor in the test equipment are obtained. The value range of the initial frequency can be 100KHZ to 200KHZ.

[0040] Specifically, an alternating current signal of an initial frequency may be applied to 35 blood samples of different concentrations and pressure volumes on 35 test strips, respectively, to obtain the impedance and phase angle of the 35 blood samples at the initial frequency collected by the sensor in the test device.

[0041] S22, obtaining a ratio of a real impedance part to an imaginary impedance part of the multiple blood samples at the initial frequency according to the impedance and phase angle of the multiple blood samples at the initial frequency; In this embodiment, the real part of impedance and the imaginary part of impedance of each of the multiple blood samples can be calculated according to the impedance and phase angle of each of the multiple blood samples at the initial frequency, and then according to the real part of impedance and the imaginary part of impedance of each of the multiple blood samples at the initial frequency, the ratio of the real part of impedance to the imaginary part of impedance of each of the multiple blood samples at the initial frequency can be obtained.

[0042] Specifically, the real impedance part R and the imaginary impedance part X of each of the 35 blood samples can be calculated according to the impedance Z and the phase angle P of each of the 35 blood samples at the initial frequency, and then according to the real impedance part R and the imaginary impedance part X of each of the 35 blood samples, the ratio R / X of the real impedance part R and the imaginary impedance part X of each of the 35 blood samples at the initial frequency can be obtained.

[0043] S23, performing linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at the initial frequency and the corresponding pressure product to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; In this embodiment, specifically, a ratio R / X of the real impedance R and the imaginary impedance X of 35 blood samples at the initial frequency is linearly fitted with the corresponding pressure product to obtain an initial linear equation of the ratio R / X of the real impedance R and the imaginary impedance X at the initial frequency and the pressure product.

[0044] S24, obtaining a linear correlation coefficient of the initial linear equation at the initial frequency according to the initial linear equation at the initial frequency; In this embodiment, the linear correlation coefficient of the initial linear equation at the initial frequency is calculated to obtain the specific value of the linear correlation coefficient of the initial linear equation at the initial frequency.

[0045] S25, determining whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; In this embodiment, the preset threshold is a pre-set threshold, and the preset threshold may be 0.99.

[0046] S26, if yes, use the initial frequency as the preset frequency; In this embodiment, if the specific value of the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to the preset threshold, the initial frequency is used as the preset frequency. Specifically, if the initial frequency is 200KHZ, according to the test results, the specific value of the linear correlation coefficient of the linear equation at the frequency of 200KHZ is 0.9937, and 0.9937 is greater than the preset threshold 0.99. Therefore, 200KHZ is used as the preset frequency.

[0047] S27, if not, adjust the frequency and repeat the above steps until the linear correlation coefficient of the linear equation under the adjusted frequency is greater than or equal to the preset threshold, and use the adjusted frequency as the preset frequency.

[0048] In this embodiment, if the specific value of the linear correlation coefficient of the linear equation at the initial frequency is less than the preset threshold, the frequency is adjusted and the above steps S31-S35 are repeated. Based on the judgment result of whether the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, it is determined whether to continue to adjust the frequency and repeat the above steps S31-S35 until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and the adjusted frequency is used as the preset frequency.

[0049] Specifically, if the initial frequency is 100KHZ, since it can be known from the test results that the specific value of the linear correlation coefficient of the linear equation at the frequency of 100KHZ is less than the preset threshold value of 0.99, the frequency can be adjusted to 101KHZ or to 110HKZ. Preferably, the frequency is adjusted to 110HKZ, and an AC signal of 110HKZ is applied to 35 blood samples of different concentrations and different pressure volumes on 35 test strips, respectively, and the impedance and phase angle of the 35 blood samples at the frequency of 110HKZ are obtained. According to the impedance and phase angle of the 35 blood samples at the frequency of 110HKZ, the ratio of the real part of the impedance to the imaginary part of the impedance of the 35 blood samples at the frequency of 110HKZ is obtained, and the ratio of the real part of the impedance to the imaginary part of the impedance of the 35 blood samples at the frequency of 110HKZ is calculated. The ratio is linearly fitted with the corresponding compressed product to obtain a linear equation of the ratio of the real part of the impedance to the imaginary part of the impedance at a frequency of 110HKZ and the compressed product. According to the linear equation at a frequency of 110HKZ, the linear correlation coefficient of the linear equation at a frequency of 110HKZ is obtained, and it is determined whether the linear correlation coefficient of the linear equation at a frequency of 110HKZ is greater than or equal to a preset threshold. According to the test results, the specific value of the linear correlation coefficient of the linear equation at a frequency of 110KHZ is less than the preset threshold of 0.99, and the frequency is continued to be adjusted until the frequency is adjusted to 200KHZ. According to the test results, the linear correlation coefficient of the linear equation at the adjusted frequency of 200KHZ is 0.9937, which is greater than the preset threshold of 0.99. Therefore, the adjusted frequency 200KHZ is used as the preset frequency.

[0050] In this embodiment, steps S21 to S27 may be performed before step S11 or before step S14.

[0051] As an implementation manner, in the embodiment of the present application, the preset frequency is preferably 200KHZ.

[0052] In this embodiment, according to the test, the higher the frequency of the alternating current signal applied to the multiple blood samples, the higher the linear correlation coefficient of the linear equation obtained by linear fitting the ratio of the real part of the impedance to the imaginary part of the impedance of the multiple blood samples and the corresponding pressure product. However, the higher the frequency, the higher the requirements for the equipment (equipment cost). Therefore, 200KHZ, in which the linear correlation coefficient meets the requirements (i.e., greater than the preset threshold), is preferred.

[0053] As an implementation manner, in the embodiment of the present application, the value range of the initial frequency is 100KHZ to 200KHZ.

[0054] In this embodiment, the value of the initial frequency may be 100KHZ, or 200KHZ, or other values ​​between 100KHZ and 200KHZ, and may be specifically set as needed.

[0055] As an implementation manner, in the embodiment of the present application, the alternating current signal is a sinusoidal alternating current signal.

[0056] In this embodiment, the sinusoidal AC signal may be: ; Where y is voltage, A is amplitude, F is frequency, and t is time; Specifically, the amplitude A may be 100 mV.

[0057] like Figure 2 As shown, the embodiment of the present application also provides a device for measuring hematocrit, including: An application module 21, used for applying an alternating current signal of a preset frequency to the blood sample to be tested; A first acquisition module 22, used to acquire the real impedance part and the imaginary impedance part of the blood sample to be tested; The first processing module 23 is used to substitute the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; A second acquisition module 24 is used to apply an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedance and phase angle of the plurality of blood samples at the preset frequency; A second processing module 25, for obtaining a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at a preset frequency according to the impedance and phase angle of the plurality of blood samples at a preset frequency; The third processing module 26 is used to perform linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of multiple blood samples at a preset frequency and the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency.

[0058] As an implementation manner, in the embodiment of the present application, the device further includes: A third acquisition module is used to apply an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedance and phase angle of the plurality of blood samples at the initial frequency; a fourth processing module, configured to obtain a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at the initial frequency according to the impedance and phase angle of the plurality of blood samples at the initial frequency; a fifth processing module, configured to linearly fit the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the initial frequency to the corresponding pressure product, to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; A sixth processing module, used for obtaining a linear correlation coefficient of the initial linear equation at the initial frequency according to the initial linear equation at the initial frequency; A judgment module, used to judge whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; a seventh processing module, configured to use the initial frequency as the preset frequency if the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; The eighth processing module is used to adjust the frequency if the linear correlation coefficient of the linear equation at the initial frequency is less than the preset threshold, until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and use the adjusted frequency as the preset frequency.

[0059] As an implementation manner, in the embodiment of the present application, the preset frequency is preferably 200KHZ.

[0060] As an implementation manner, in the embodiment of the present application, the value range of the initial frequency is 100KHZ to 200KHZ.

[0061] As an implementation manner, in the embodiment of the present application, the alternating current signal is a sinusoidal alternating current signal.

[0062] The embodiments in this specification are described in a progressive manner, and each embodiment focuses on the For the differences between other embodiments, the same or similar parts between the embodiments may be referred to each other.

[0063] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for measuring hematocrit, characterized in that: include: Applying an alternating current signal of a preset frequency to the blood sample to be tested; Obtaining the real impedance part and the imaginary impedance part of the blood sample to be tested; Substituting the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; Wherein, the preset linear equation is obtained by the following method: Applying an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedance and phase angle of the plurality of blood samples at the preset frequency; Obtaining a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at a preset frequency according to the impedance and phase angle of the plurality of blood samples at a preset frequency; The ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the preset frequency is linearly fitted with the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency.

2. The method according to claim 1, characterized in that The preset frequency is determined by the following method: Applying an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to obtain impedances and phase angles of the plurality of blood samples at the initial frequency; Obtaining a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at the initial frequency according to the impedance and phase angle of the plurality of blood samples at the initial frequency; Performing a linear fit on the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the initial frequency and the corresponding pressure product to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; According to the initial linear equation at the initial frequency, a linear correlation coefficient of the initial linear equation at the initial frequency is obtained; Determining whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; If yes, the initial frequency is used as the preset frequency; If not, the frequency is adjusted and the above steps are repeated until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and the adjusted frequency is used as the preset frequency.

3. The method according to claim 1 or 2, characterized in that: The preset frequency is preferably 200KHZ.

4. The method according to claim 2, characterized in that: The value range of the initial frequency is 100KHZ to 200KHZ.

5. The method according to claim 2, characterized in that: The alternating current signal is a sinusoidal alternating current signal.

6. A device for measuring hematocrit, characterized in that: include: An application module, used for applying an alternating current signal of a preset frequency to the blood sample to be tested; A first acquisition module is used to acquire the real impedance part and the imaginary impedance part of the blood sample to be tested; A first processing module, used for substituting the ratio of the real part of the impedance to the imaginary part of the impedance into a preset linear equation to obtain the hematocrit of the blood to be tested; A second acquisition module, used to apply an alternating current signal of a preset frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to acquire impedance and phase angle of the plurality of blood samples at the preset frequency; A second processing module, configured to obtain a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at a preset frequency according to the impedance and phase angle of the plurality of blood samples at a preset frequency; The third processing module is used to perform linear fitting on the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at a preset frequency and the corresponding pressure product to obtain a preset linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the preset frequency.

7. The device according to claim 6, characterized in that The device also includes: A third acquisition module is used to apply an alternating current signal of an initial frequency to a plurality of blood samples of different concentrations and different pressure volumes, respectively, to acquire impedance and phase angle of the plurality of blood samples at the initial frequency; a fourth processing module, configured to obtain a ratio of a real impedance part to an imaginary impedance part of the plurality of blood samples at the initial frequency according to the impedance and phase angle of the plurality of blood samples at the initial frequency; a fifth processing module, configured to linearly fit the ratio of the real part of impedance to the imaginary part of impedance of the plurality of blood samples at the initial frequency to the corresponding pressure product, to obtain an initial linear equation of the ratio of the real part of impedance to the imaginary part of impedance and the pressure product at the initial frequency; A sixth processing module, configured to obtain a linear correlation coefficient of the initial linear equation at the initial frequency according to the initial linear equation at the initial frequency; A judgment module, used to judge whether the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; a seventh processing module, configured to use the initial frequency as the preset frequency if the linear correlation coefficient of the linear equation at the initial frequency is greater than or equal to a preset threshold; The eighth processing module is used to adjust the frequency if the linear correlation coefficient of the linear equation at the initial frequency is less than the preset threshold, until the linear correlation coefficient of the linear equation at the adjusted frequency is greater than or equal to the preset threshold, and use the adjusted frequency as the preset frequency.

8. The device according to claim 6 or 7, characterized in that The preset frequency is preferably 200KHZ.

9. The device according to claim 7, characterized in that The value range of the initial frequency is 100KHZ to 200KHZ.

10. The device according to claim 7, characterized in that The alternating current signal is a sinusoidal alternating current signal.

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