CN102818822A - Diagnostic device and method for measuring prothrombin time and hematocrit (HCT%) by analyzing reactance changes in samples - Google Patents

Abstract

The invention discloses a diagnostic device and method for measuring prothrombin time and hematocrit (HCT%) by analyzing reactance change. The diagnostic device for measuring hematocrit and/or prothrombin time includes: a counter electrode type sensor device; and a test card assembly comprising one or more pairs of working electrodes; wherein an Alternating Current (AC) signal is provided by the sensor device for measuring and calculating prothrombin time and hematocrit in a blood test by reactance analysis.

Description

Diagnostic device and method for measuring prothrombin time and hematocrit (HCT%) by analyzing reactance changes in samples

Cross references to related applications

This application is U.S. Provisional Patent Application No. 61/353,137, filed June 9, 2010, entitled "Diagnostic Apparatus and Method for Measuring Prothrombin Time and Hematocrit (HCT%) Using Analytical Reactance Changes" The non-provisional patent application of , which is hereby incorporated by reference in its entirety.

technical field

The invention relates to a biochemical detection device, in particular to a diagnostic device and method for measuring prothrombin time and hematocrit (HCT%) by analyzing reactance changes.

Background technique

Human blood coagulation reaction can be divided into extrinsic pathway (extrinsic pathway) and intrinsic pathway (intrinsic pathway). When the human body is injured, the external pathway will first be activated to control the blood coagulation reaction in the body. In addition to blood, the blood coagulation reaction needs tissue factor (tissue factor), which catalyzes the inactive factor X (factor X) into factor Xa ( factor Xa). Furthermore, factor Xa turns prothrombin (prothrombin, factor II) into thrombin (thrombin, factor IIa) through the action of factor Va (factor Va), acid phospholipids and calcium ions, and thrombin turns fibrinogen ( fibrinogen) into fibrin, which strengthens the aggregation of platelets at the injured endothelial cells, and thrombin can also enhance the action of factor XIII, linking different fibrin molecules and stabilizing fibrin. Therefore, the prothrombin time (prothrombin time) examination can not only be used as a pointer to detect whether the function of the coagulation system activated by external factors is normal, but also can be used to observe oral anticoagulant therapy, liver function, lack of vitamin K, lack of coagulation factors, Evaluation and monitoring of disseminated intravascular coagulation (DIC).

A known method for detecting blood coagulation time is to analyze the coagulation phenomenon caused by the transformation of soluble protein in the serum into insoluble protein when blood coagulates, and to perform detection using optical methods such as color change, reflection, refraction, luminescence, and fluorescence. This analysis method requires a large amount of blood samples and high-purity reagents and takes a long time, as shown in US Patent No. 5,418,141. However, these detection methods require a long detection time and a lot of consumables, which is really inconvenient.

Another known electrochemical detection method, U.S. Patent No. 3,699,437, is to observe the drop rate of impedance from the initial point to the lowest point, and use its calculation results as the basis for judging blood coagulation. ) signal as a coagulation measurement mechanism. After that, there are also U.S. Patents No. 6,060,323, No. 6,338,821, No. 6,066,504, No. 6,673,622, and No. 6,046,051, etc., which disclose the design of a single electrode or multiple electrodes according to the measurement requirements, and use the viscosity of blood before and after coagulation The method of measuring the coagulation of blood samples by the method of impedance change caused by the difference of degree. However, this technique can lead to measurement errors due to differences in hematocrit and blood electrolyte concentrations between individuals. Furthermore, US Patent No. 7,005,857 discloses a blood coagulation detection device including automatic blood collection. The detection mechanism is to measure the change of capacitance or impedance between two electrodes to determine the blood coagulation time. Therefore, these technologies greatly improve the simplicity of detection, but cannot achieve the detection accuracy of optical methods.

In view of this, it is necessary to provide a biosensor capable of rapid detection, convenient use and high accuracy for measuring prothrombin time (PT) and hematocrit (HCT%).

Contents of the invention

In view of this, an object of the present invention is to provide a method for measuring blood by using reactance (X). The reactance analysis can provide more accurate blood property analysis, effectively reduce test errors and improve measurement accuracy.

Another object of the present invention is to provide a detection system for measuring prothrombin time and HCT% by reactance analysis. The system includes a sensor and a test piece, which means that the test piece contains a pair or plural pairs of precious metals. The electrodes are respectively arranged on the same plane or on different planes, and the sensor is used to provide an alternating current (AC), and the prothrombin time and HCT% are measured and calculated by the reactance analysis method.

Another object of the present invention is to provide a test card assembly that can increase the contact area between blood and reaction reagents. According to some embodiments of the present invention, the test card assembly uses a porous material, such as fiberglass board (FR-4), as at least a part of the test card substrate. Since at least a part of the test card substrate, preferably the entire surface has porosity, for example, a plurality of holes, holes, and cavities may be formed on its surface, so the material can disperse blood better and evenly, thereby increasing The contact area between blood and reagents can effectively improve the shortcomings of traditional non-porous materials. According to the present invention, it can effectively reduce or eliminate the problem of poor contact surface between blood and reagents due to the increase of blood cohesion caused by the use of non-porous substrates.

According to one aspect of the present invention, there is provided a diagnostic device for measuring hematocrit (HCT%) and/or prothrombin time, which includes an opposing electrode type sensor device; and a test card assembly, including one or more pairs of working electrodes; Wherein the sensor device provides an alternating current (AC) signal to measure and calculate the prothrombin time and the hematocrit ratio in the blood test by reactance analysis.

In one embodiment, the sensor device includes a test card accommodating unit to accommodate the test card assembly; a temperature maintaining unit to control and maintain the test card accommodating unit to a constant temperature; the AC signal generating unit provides alternating current of frequency and voltage to The test card component; a signal receiving unit, which intercepts the response signal from the test card component; a processor calculates the response signal and obtains the results of the hematocrit ratio and the prothrombin time; and a display unit, which displays the response signal from the micro The detection results of the hematocrit ratio and the prothrombin time calculated by the processor.

According to another aspect of the present invention, there is provided a method for measuring hematocrit (HCT%) and prothrombin time, which includes providing a test card assembly to a test card accommodating unit; controlling and maintaining the temperature of the test card accommodating unit to a constant temperature; provide the sample to be tested to the test card component; provide alternating current with a specific frequency and voltage to the test card component from the AC signal generating unit; receive the response signal from the test card component, and calculate the response signal by the microprocessor obtaining the hematocrit ratio and the prothrombin time; and providing the detection results to the display unit for display.

Description of drawings

FIG. 1 shows a schematic block diagram of a diagnostic device for measuring hematocrit (HCT) and/or prothrombin time according to some embodiments of the present invention.

Fig. 2 shows an exploded schematic diagram of a blood test card assembly according to an embodiment of the present invention, wherein the dotted lines indicate the relative positions of various components.

Figures 3A and 3B side by side show the microstructural photographs of the test card components without holes and substrates with holes observed by electron microscope.

FIG. 4 is a flowchart showing a diagnostic method for measuring hematocrit (HCT%) and prothrombin time according to an embodiment of the present invention.

Fig. 5 shows a plot of experimental data of impedance change versus coagulation time (seconds), which represents the change in slope when a bulk blood sample is coagulated, as measured by a general impedance measurement method.

Figure 6 shows an experimental data plot of reactance change versus coagulation time (seconds), which represents the change in slope as measured by reactance measurements as a bulk blood sample coagulates.

Figures 7 and 8 show plots of experimental data representing a calibration curve for PT vs. impedance change rate (Figure 7) and a calibration curve for PT vs. reactance rate of change (Figure 8), respectively.

Figures 9 and 10 show an example where impedance and reactance values are measured every 0.5 seconds for 60 seconds by an LCR meter.

Figures 11 and 12 show experimental examples, which represent a calibration curve of PT versus impedance change rate and a calibration curve representing PT versus reactance change rate, respectively.

Figures 13 and 14 show plots of experimental data representing corrected PT versus real PT measured by impedance and representing corrected PT versus real PT measured by reactance, respectively.

Figures 15A and 15B show graphs of experimental data representing coagulation assays performed on the porous and non-porous substrates of the test card, respectively.

Figures 16A-16C show graphs of experimental data, respectively representing blood coagulation analysis performed at different frequencies by reactance measurement according to embodiments of the present invention.

Explanation of main component symbols

100 diagnostic devices

110 test card components

120 sensor devices

122 test card accommodation unit

124 AC signal generation unit

126 phase angle calculation unit

128 signal receiving unit

130 microprocessors

132 temperature sensor

134 temperature maintenance unit

136 display units

210 insulating substrate

220 electrode system

222 sample area

224 reaction area

225 test electrodes

226 working electrode

228 reference electrode

230 separate layers

232 spacers

236 channels

240 top cover

242 import port

244 Vent

S410-S480 Procedures for measuring hematocrit and prothrombin time

In order to make the present invention more comprehensible, the specific examples below are described in detail in conjunction with the attached drawings as follows:

Detailed ways

Hereinafter, a plurality of embodiments are described in detail and examples accompanied by drawings are used as a reference basis of the present invention. In the drawings or descriptions in the specification, the same figure numbers are used for similar or identical parts. And in the drawings, the shape or thickness of the embodiments may be exaggerated and marked for clarity or convenience. Furthermore, parts of the components in the drawings will be described separately. It should be noted that the components not shown or described in the drawings are forms known to those skilled in the art. Furthermore, when it is described that a layer is "on" another layer or a substrate, it may mean that it is directly on the other layer or substrate, or it may mean that an intervening layer exists therebetween.

Some implementation examples of the present invention are not described in more detail along with the drawings of this application. It should be noted that the features shown in the drawings are not drawn to a certain scale. Well-known components, materials and processing techniques may be omitted to avoid unnecessarily obscuring the embodiments of the invention. The components, materials and process technologies described in these embodiments are only descriptions used to disclose the present invention, and are not intended to limit the present invention.

In view of the above-mentioned known technical problems, the following embodiments provide a system for measuring prothrombin time and hematocrit (HCT%) by using reactance analysis, also known as a reactance measurement module. More specifically, a detection system can be used to improve specimen loading characteristics and measurement accuracy. The use of reactance for the analysis of blood coagulation measurement characteristics or hematocrit ratio detection is better applied to the quantitative analysis of coagulation time. Hereinafter, the hematocrit generally refers to the percentage of red blood cell thick liquid in the volume of the whole blood.

An embodiment of the present invention provides a counter electrode sensor device, which has a test card including one or more pairs of working electrodes. The substrate of the test card can be made of porous material or non-porous material. The working electrode can be made of precious metals, including but not limited to: gold (Au), silver (Ag), palladium (Pd), platinum (Pt), alloys of the above metals, and any combination of the above metals. In one aspect of the present invention, an alternating current module or an alternating current and direct current module is used to provide a test signal to the blood test card to have a frequency oscillation, the frequency range is about 0.1KHz to about 50KHz, and the voltage is supplied to perform For reactance measurements, the voltage range may be from about 0.05V to about 5V. As in the examples herein in relation to the measured quantities, the term "about" refers to those skilled in the art who carry out the measurements and carefully operate the measuring equipment, and use the measuring equipment to achieve the measurement purpose and measurement accuracy that can be expected The measured value change achieved.

In a preferred aspect, when the reaction between the enzyme and the blood causes blood coagulation, the reaction signal received and processed by the sensor device is mainly analyzed according to the difference in slope caused by the length of time in the coagulation process. In one embodiment, the electrodes may be gold electrodes. In this specific embodiment, an AC module is used to perform reactance measurement according to the oscillating test signal responded from the blood test card, wherein when the reaction between the enzyme and the blood causes blood coagulation, the reaction received and processed by the sensor device The signal is mainly based on the difference in slope caused by the length of time in the coagulation process for reactance analysis.

The principle of reactance measurement according to some embodiments of the present invention is as follows. In an AC circuit (ACcurcuit), impedance is the sum of resistance (R) plus reactance (X) times the phase angle (θ), as shown in the following formula:

Among them, the reactance (X) is the imaginary part of the complex impedance (Z), which is used to represent the resistance of the inductance (L) and the capacitance (C) to the current, and the resistance (R) is the real part of the complex impedance. As is known to those of ordinary skill in the art, reactance varies with frequency of an AC circuit, with capacitance and/or with inductance. When the reactance in the AC circuit changes, the phase of the current waveform and the voltage waveform of the AC circuit also changes accordingly. The impedance is defined as:

Z=R+jX, and |Z|=(R ² +Z ² ) ^1/2 (1)

where Z is impedance (impedance), R is resistance (resistance), j is phase angle, and X is reactance (reactance); and

X=X _C +X _L , X _L =2πfL, and X _C =1/2πfC (2)

Where X _C is a capacitor reactance, X _L is an inductor reactance, is the circumference ratio, f is a frequency, L is an inductance, and C is a capacitance.

In an embodiment aspect, in operation, the AC signal generation unit of the testing system provides an alternating current (AC) test signal. When the blood sample is between the electrodes, the induced charges will move under force in the electric field to form capacitance. When the blood sample coagulates, a medium is formed between the working electrodes, thereby hindering the movement of charge and allowing charge to accumulate on the conductor. This accumulated charge can lead to capacitive reactance. In a preferred aspect, the frequency (f) provided by the AC signal generating unit of the detection system is a constant value, so the inductance (L) and inductive reactance (XL) are also constant values, so the variation of the capacitive reactance (XC) Equal to the change in reactance, as shown in the following formula.

X _C2 -X _C1 =X ₂ -X ₁ (3)

Among them, X _C2 -X _C1 is the variation of capacitive reactance (X _C ), and X ₂ -X ₁ is the variation of reactance.

By measuring the change of reactance per unit time, the change of capacitive reactance per unit time and the change of capacitance per unit time can be known when blood coagulates. With the assistance of the reactance measurement module of the present invention, the length of the thromboplastin time (blood clotting time) can be analyzed through slope calculation.

FIG. 1 shows a schematic block diagram of a diagnostic device for measuring hematocrit (HCT) and/or prothrombin time according to some embodiments of the present invention. As shown in FIG. 1, a diagnostic device 100 for measuring hematocrit (HCT) and/or prothrombin time includes an opposing electrode type sensor device 120 and a test card assembly 110 with one or more pairs of working electrodes, wherein The sensor device provides an alternating current (AC) signal to measure and calculate prothrombin time and hematocrit in blood tests by reactance analysis. The sensor device 120 includes a test card accommodating unit 122 to accommodate the test card assembly 110, a temperature maintaining unit 134 to control and maintain the test card accommodating unit to a constant temperature, and an AC signal generating unit 124 to provide alternating current of frequency and voltage to the Test card assembly 110, the signal receiving unit 128 intercepts the response signal from the response of the test card assembly, the microprocessor 130 calculates the response signal and obtains the results of the hematocrit ratio and the prothrombin time, and the display unit 136 displays the results from the test card assembly. The detection result of the hematocrit and/or the prothrombin time calculated by the microprocessor 130 .

FIG. 2 is an exploded schematic diagram of a blood test card assembly according to an embodiment of the present invention, wherein the dotted lines indicate the relative positions of various components. The blood test card assembly includes an insulating substrate 210 , an electrode system 220 , a separation and reaction layer 230 , and a top cover 240 . The insulating substrate 210 is electrically insulating, and its material may include but not limited to a substrate made of porous material. In one embodiment, the substrate of the test card assembly includes a plurality of holes, the diameters of which range from approximately 0.1 μm to approximately 10 μm, approximately 0.01 μm to approximately 100 μm, approximately 0.1 μm to approximately 50 μm, approximately 0.1 μm to approximately 20 μm, From about 0.1 μm to about 5 μm, or from about 5 μm to about 10 μm. The electrode system 220 may be made of any conductive material, including but not limited to carbon, gold-silver, copper, carbon-silver, palladium, platinum, nickel, other similar materials, or any combination thereof. The electrode system 220 may include one or more pairs of noble metal electrodes, respectively disposed on the same or different planes. For example, set of test electrodes 225 includes a pair of electrodes 226,228. According to the principles of the present invention, the above configuration does not limit the arrangement of the test electrodes 225 in a specific configuration, or limit the number of electrodes. Additional electrodes are also available according to different application requirements. The electrode system is further electrically connected to the electrode system (not shown) of the measuring device.

The illustrated separator layer 230 includes spacers 232 disposed above the electrode system 220 . The separation layer 230 may further include a reaction area 224 , an exposed part of the reaction reagent (not shown) and the sample area 222 . The channel 236 can communicate the sample area 222 and the reaction area 224 . The size of the reaction area 224 is preferably sufficient to expose portions of the electrodes 226 and 228 . In this embodiment, the reaction area 224 is an area for measuring prothrombin time, and the sample area 222 is an area for measuring hematocrit.

The top cover layer 240 is disposed above the separation layer 230 . In one embodiment, the top cover layer 240 may include an introduction port 242 and an exhaust hole 244 , which are respectively connected to the sample area 222 and the reaction area 224 . The size of the sample space is determined by the thickness of the separation layer 230 .

Figures 3A and 3B show microstructure photographs of the test card components without holes and substrates with holes observed by electron microscope, respectively. In Figure 3B, it is shown that the diameter of the holes can range from about 0.1 μm to about 10 μm, with an average diameter of about 3.39 m; and the average distribution of holes is about 5.04×106 holes/cm2 holes.

FIG. 4 is a flowchart showing a diagnostic method for measuring hematocrit (HCT) and prothrombin time according to an embodiment of the present invention. The method for measuring hematocrit (HCT) and prothrombin time includes providing a test card assembly to a test card accommodating unit (step S410); controlling and maintaining the temperature of the test card accommodating unit to a constant temperature (step S420 ); provide the sample to be tested to the test card component (step S430); provide the alternating current of specific frequency and voltage to the test card component by the AC signal generating unit (step S440); obtain a response from the test card component in response to the AC signal signal, compare the response signal with the AC signal, calculate the phase angle change (phase angle offset) of the AC signal, and calculate the capacitance and the hematocrit ratio by the microprocessor (step S450); convert the capacitance with an algorithm and refer to The hematocrit ratio is corrected to the prothrombin time (step S460); the prothrombin time is corrected by an AC signal generating unit with an international normalized ratio (internationalnormalized ratio, INR) (step S470); and the detection result is provided to The display unit displays (step S480).

According to some embodiments of the present invention, the response signal is digitized and subjected to discrete Fourier transformation (DFT). Therefore, the calculation methods of the real number part and the imaginary number part are respectively expressed as follows.

$x\left(k\right)=\mathrm{DFT}\left[x\left(\mathrm{no}\right)\right]=\underset{\mathrm{no}=0}{\overset{N-1}{\mathrm{\Σ}}}x\left(\mathrm{no}\right)W_N^{\mathrm{k\; n}},$ 0≤k≤N-1 (1)

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; N</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; <figure-callout\; id="2"\; label="j"\; filenames="HDA0000093736620000081.png,HDA0000093736620000091.png"\; state="\{\{state\}\}">j</figure-callout></span>}\frac{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}}{\mathrm{<span\; class="notranslate">\; N</span>}}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Where X(k) is the Fourier value of the digital signal, x(n) is the original value of the digital signal, n is the current point of the digital signal, and N is the total number of digital signals. Furthermore, the phase angle can be obtained by calculating the real and imaginary parts according to the following formula:

Phase angle＝tan-1(Im/Re)         (3)

where Im is an imaginary value (such as reactance) and Re is a real value (such as resistance). As shown in equation (3) above, the phase angle will shift as the reactance changes in the sample.

In some embodiments, in the description of step S450 above, the step of comparing the response signal detected from the sample with the original AC signal includes: calculating the amount of reactance from the measured response signal and the applied voltage; calculating the applied voltage waveform and the measured waveform The phase angle change between ; reactance is calculated from the phase angle change. It will be appreciated that since the alternating current has a fixed frequency, changes in the phase angle as previously described can be attributed to changes in capacitance in the sample. Since changes in capacitance in the sample result in changes in reactance, HCT and prothrombin time (PT) can be calculated from changes in reactance, as discussed further below.

From the measured reactance, HCT can be calculated by interpolation. A specific example of calculating the hematocrit ratio is described below. The traditional method of calculating hematocrit using impedance is also described as a comparative example.

Figures 5 and 6 show plots of experimental data showing impedance and reactance, respectively, as a function of higher hematocrit. As shown in the data plot of Figure 6, in this particular example, the reactances at 11 seconds for the different HCTs (29.3 and 47%) were 620.29, 625.17 and 676.59 ohms, respectively. Next, calculate the relationship between HCT and impedance (Figure 7) or the relationship between HCT and reactance (Figure 8). As shown in FIG. 5 , in this specific example, the optimal impedance sampling time of HCT is about 20 seconds or more, and the calibration curve of impedance vs. HCT conforms to the formula y=90.253x+2347.7. Furthermore, as shown in Figure 6, the optimal impedance sampling time of HCT is about 11 seconds or more, and the calibration curve of reactance versus HCT conforms to the formula y=3.1304x+529.68. It should be understood that x represents HCT and y represents impedance or reactance.

Figures 9 and 10 show an example where impedance and reactance values are measured every 0.5 seconds for 60 seconds by an LCR meter. In one example, whole blood and various samples are collected from a subject by adding different amounts of anticoagulant (heparin) to the whole blood collected. For example, the concentration of heparin used to modulate the clotting time (PT) is approximately between 1 U and 30 U per milliliter. Then, the blood samples with different PTs were analyzed by LCR meter (HiokiModel No. 3532-50) to measure impedance or reactance.

Figures 11 and 12 show experimental examples, which represent a calibration curve of PT versus impedance change rate and a calibration curve representing PT versus reactance change rate, respectively. In this particular example, the rate of change of impedance or reactance can be calculated by an LCR meter in US 10 seconds. For example, the change rate between 30 and 40 seconds can be obtained by the following formula: Impedance change rate 30 to 40=(Z40-Z30)/(Time40-Time30), where Z is the impedance, and Reactance change rate 30 to 40= (X40-X30)/(Time40-Time30), where X is reactance. The calculation step is to repeatedly calculate the impedance and reactance rate of change of blood samples with different PTs, and thus determine the calibration curve of PT vs. impedance rate of change (Fig. 7) and the calibration curve representing PT vs. reactance rate of change (Fig. 8) . The correction curve of the PT to the impedance change rate conforms to the formula y=-0.1849x+4.562, and the correction curve of the PT to the reactance change rate conforms to the formula y=-0.0256x+0.3604. It should be understood that x represents a real number PT and y represents a rate of change of impedance or reactance.

As shown in Figures 11 and 12, the diagnostic results of the reactance measurement method (Figure 12) showed a better standard deviation (SD value) compared with the diagnostic results of the traditional impedance measurement method (Figure 11). More specifically, the advantage of using the reactance measurement method according to the present invention is that the standard deviation of the reactance measurement method can be significantly reduced, and in this example it is about 0.9986. In view of this, the reactance measurement method is more accurate than the general traditional impedance measurement method, and even if the blood coagulation process is prolonged, the deviation of the slope is acceptable, so it is easier to correct the value.

On the other hand, in this particular example, the linear regression value (R2) of the calibration curve of PT vs. impedance change rate is about 0.939, as shown in FIG. 11 . For this reason, impedance measurements are more likely to lead to inaccurate measurements.

In the above example, the impedance and reactance of a blood sample can be measured by the LCR meter, and the impedance change rate and reactance change rate can be calculated respectively. More specifically, HCT is calculated by using the HCT calibration curve according to the following formula: HCT=(impedance-2347.7)/90.253 or HCT=(reactance-529.68)/3.1304. Next, the real number PT is calculated from the PT calibration curve. Different HCTs may correspond to different PT calibration curves. In this particular example, PT is calculated by using the PT calibration curve according to the following formula: PT=(impedance change rate-4.562)/-0.1849 or PT=(reactance change reate-0.3604)/-0.0256.

Figures 13 and 14 show plots of experimental data representing corrected PT versus real PT measured by impedance and representing corrected PT versus real PT measured by reactance, respectively. The PT values calculated by the calibration curve were compared with the real PT values measured by an automatic blood coagulation analyzer (Sysmex CA-500 series).

The increase or decrease in HCT affects the values of prothrombin time (PT) and impedance or rate of change of reactance. More specifically, a higher HCT results in an increase in the value of the impedance or reactance rate of change. Therefore, in some embodiments, the PT measurement procedure may include an HCT correction step. Accordingly, devices according to some embodiments of the present invention include an internal memory for storing interpolated values between said HCT and impedance changes.

In one aspect of the present invention, the PT value calculated by the above example can be corrected by the international normalized ratio (INR), as shown in the following formula:

$\mathrm{<span\; class="notranslate">\; INR</span>}<span\; class="notranslate">\; =</span>{<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; PatientPT</span>}}{\mathrm{<span\; class="notranslate">\; Mean\; PT</span>}}<span\; class="notranslate">\; )</span>}^{\mathrm{<span\; class="notranslate">\; ISI</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

Where INR is the international normalized ratio, PT is the prothrombin time, and ISI is the international sensitivity index.

Figures 15A and 15B show graphs of experimental data representing coagulation assays performed on the porous and non-porous substrates of the test card, respectively. As shown in the figure, analysis with porous substrates gives better results.

Figures 16A-16C show graphs of experimental data, respectively representing blood coagulation analysis performed at different frequencies by reactance measurement according to embodiments of the present invention. Measure the coagulation time between 15 seconds and 50 seconds for blood samples, and provide measurement frequencies of 0.1kHz, 10kHz, and 50kHz. The R2 values obtained by regression analysis are 0.9636, 0.9923, and 0.9828 respectively. In this example, it was shown by regression analysis that a higher accuracy rate can be obtained using measurement frequencies of 10 kHz and 50 kHz compared to a frequency of 0.1 kHz.

Although the present invention is disclosed above with various embodiments, it is not intended to limit the scope of the present invention. Anyone with ordinary knowledge in the technical field can make some changes without departing from the spirit and scope of the present invention. with retouching. The scope of protection of the present invention should be defined by the scope of the appended patent application.

Claims (17)

1. A diagnostic device for measuring hematocrit and/or prothrombin time, comprising: Opposite electrode type sensor devices; and A test card assembly, including one or more pairs of working electrodes; Wherein the sensor device provides an alternating current (AC) signal to measure and calculate the prothrombin time and/or hematocrit in the blood test by reactance analysis. 2. The diagnostic device of claim 1, wherein the reactance analysis comprises: A response signal is obtained from the test card component in response to the AC signal, the response signal is compared with the AC signal, the phase angle change of the AC signal is calculated, and the capacitance and the hematocrit are calculated. 3. The diagnostic device of claim 2, wherein the reactance analysis further comprises: Calculate capacitance; and The capacitance is converted by an algorithm and corrected to the prothrombin time with reference to the hematocrit. 4. The diagnostic device of claim 3, wherein the reactance analysis further comprises correcting the prothrombin time with an international normalized ratio (INR). 5. The diagnostic device as claimed in claim 1, wherein the test card assembly comprises one or more pairs of noble metal electrodes, respectively disposed on the same plane or on different planes. 6. The diagnostic device of claim 1, wherein the test card assembly includes a substrate comprised of a porous material. 7. The diagnostic device as claimed in claim 6, wherein the substrate of the test card assembly has holes with diameters ranging from approximately 0.1 microns to 10 microns. 8. The diagnostic device of claim 1, wherein the sensor device comprises: a test card accommodating unit for accommodating the test card assembly; A temperature maintaining unit is used to control and maintain the test card accommodating unit to a constant temperature; The AC signal generating unit provides alternating current of frequency and voltage to the test card component; a signal receiving unit, intercepting a response signal from the test card component; the microprocessor calculates the response signal and obtains the results of the hematocrit and the prothrombin time; and A display unit displays the detection results of the hematocrit and the prothrombin time calculated by the microprocessor. 9. The diagnostic device of claim 8, wherein the microprocessor compares the response signal with the original AC signal, calculates the phase angle change of the AC signal, and calculates capacitance and the hematocrit. 10. The diagnostic device of claim 9, wherein the microprocessor further converts the capacitance with an algorithm, corrects the prothrombin time with reference to the hematocrit ratio, and corrects the prothrombin time with an international normalized ratio . 11. A method of measuring hematocrit and/or prothrombin time comprising: providing the test card assembly to the test card accommodating unit; controlling and maintaining the temperature of the test card holding unit to a constant temperature; providing a sample to be tested to the test card component; The AC signal generating unit provides alternating current of a specific frequency and voltage to the test card component; receiving a response signal from the test card component, and calculating the response signal by the microprocessor to obtain the hematocrit and/or the prothrombin time; and The detection result is provided to the display unit for display. 12. The method for measuring hematocrit (HCT%) and prothrombin time as claimed in claim 11, wherein said test card component receives a response signal, and calculates the response signal by a microprocessor to obtain the hematocrit The ratio and/or the prothrombin time steps include: A response signal is obtained from the test card component in response to the AC signal, the response signal is compared with the AC signal, the phase angle change of the AC signal is calculated, and the capacitance and the hematocrit are calculated. 13. The method for measuring hematocrit and prothrombin time as claimed in claim 12, wherein the test card component receives a response signal, and the microprocessor calculates the response signal to obtain the hematocrit and/or The prothrombin time steps also include: Calculate capacitance; and The capacitance is converted by an algorithm and corrected to the prothrombin time with reference to the hematocrit. 14. The method for measuring hematocrit and prothrombin time as claimed in claim 13, wherein the step of receiving a response signal from the test card component and calculating the response signal by a microprocessor to obtain the prothrombin time ,Also includes: The prothrombin time was corrected by the international normalized ratio (INR). 15. The method for measuring hematocrit and prothrombin time as claimed in claim 11, wherein the test card assembly comprises one or more pairs of noble metal electrodes, which are respectively arranged on the same plane or on different planes. 16. The method for measuring hematocrit and prothrombin time as claimed in claim 11, wherein the test card assembly comprises a substrate made of a porous material. 17 . The method for measuring hematocrit and prothrombin time as claimed in claim 11 , wherein the substrate of the test card assembly has holes with diameters ranging from approximately 0.1 μm to 10 μm.

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