DEVICE AND METHOD FOR MEASURING PROTHROMBIN TIME AND HEMATOCRIT BY ANALYZING CHANGE IN REACTANCE IN A SAMPLE

• US 20110303556A1
• Filed: 06/09/2011
• Published: 12/15/2011
• Est. Priority Date: 06/09/2010
• Status: Active Grant

• Current Assignee: Apex Biotechnology Corporation
• Original Assignee: Apex Biotechnology Corporation
• Inventors: Lin, Yueh-Hui, Chu, Ching-Yuan, Cheng, Chu-Ming, Chen, Sz-Hau, Chen, Guan-Ting, Lu, Yi-Chen, Shen, Thomas Y.S,
• Granted Patent: US 8,828,322 B2
• Time in Patent Office: Days
• US Class Current: 205/792
• CPC Class Codes: G01N 27/447 using electrophoresis
• CPC Class Codes: G01N 2800/224 Haemostasis or coagulation
• CPC Class Codes: G01N 33/4905 Determining clotting time of blood by chemical methods G01N33/86, C12Q1/54
• CPC Class Codes: Y10T 436/11 Automated chemical analysis

Abstract

Devices and methods for measuring prothrombin time (PT) and hematocrit (HCT) by analyzing the change in reactance in a sample are presented. A diagnostic device for measuring HCT and PT of a fluid includes a relative electrode-type sensor device and a blood test card assembly including one or more pairs of electrodes, wherein alternating current (AC) provided by the sensor device is used to measure and calculate HCT and PT of blood test using the reactance analysis.

Claims

1. A diagnostic device for measuring hematocrit (HCT) and/or prothrombin time (PT) of a sample, comprising:

an electrode-type sensor device;

a test card assembly including one or more pairs of electrodes;

a power source for providing an AC test signal at a constant frequency to electrodes of the test card assembly;

a signal retrieving unit coupled to the test card assembly;

a phase angle calculating unit;

a microprocessor in the sensor device programmed for analyzing a response signal from the test card assembly, an output from the phase angle calculating unit and performing a reactance analysis of a sample provided on the test card assembly; and

a display for displaying PT and/or HCT of the sample.

2. The diagnostic device as claimed in claim 1, wherein the reactance analysis comprises:

comparing a response signal from the test card assembly in response to the AC test signal and calculating a change in phase of the AC test signal, and calculating a reactance and the HCT.

3. The diagnostic device as claimed in claim 2, wherein the reactance analysis further comprises:

calculating reactance due to a change in capacitance in the sample, and

transforming the change in capacitance with algorithms and correcting to the PT by reference of the HCT.

4. The diagnostic device as claimed in claim 2, wherein the reactance analysis further comprises correcting the PT with an international normalized ratio.

5. The diagnostic device as claimed in claim 1, wherein the test card assembly comprises one or more pairs of the noble metal electrodes, set on the same plane.

6. The diagnostic device as claimed in claim 1, wherein the test card assembly comprises one or more pairs of the electrodes, set on different planes.

7. The diagnostic device as claimed in claim 1, wherein the test card assembly comprises a base plate comprising a porous material that includes holes, voids or cavities thereon.

8. The diagnostic device as claimed in claim 7, wherein the base plate of the test card assembly comprises pores such as holes, voids or cavities thereon, with diameters approximately in a range of about 0.1 μ

m to about 10 μ

m.

9. The diagnostic device as claimed in claim 8, wherein the microprocessor further transforms the capacitance with algorithms, corrects to the PT by reference of the HCT;

and calculates the PT with an international normalized ratio.

10. A method for measuring hematocrit (HCT) and/or prothrombin time (PT) of a sample, comprising:

providing a test card assembly to a test card receiving unit;

providing a sample to be inspected to the test card assembly;

providing an alternating current with predetermined frequency and voltage to the test card assembly by an AC generation unit;

receiving a response signal from the test card assembly;

performing a reactance analysis of the sample;

determining the HCT and/or the PT with a microprocessor; and

providing an inspected result to a display unit.

11. The method as claimed in claim 10, wherein the step of receiving a response signal from the test card assembly and calculating the HCT and/or the PT by a microprocessor comprises:

receiving a response signal from the test card assembly, comparing the response signal with an original AC signal, calculating a change in phase, and calculating a reactance and the HCT by a microprocessor.

12. The method as claimed in claim 10, wherein the method further comprises:

calculating a reactance caused by a change in capacitance in the sample, and

transforming the reactance with algorithms and correcting to the PT by reference of the HCT.

13. The method as claimed in claim 12, wherein the method further comprises:

correcting the PT with an international normalized ratio.

14. The method as claimed in claim 10, wherein the test card assembly comprises one or more pairs of the noble metal electrodes, set on the same plane or on different planes respectively.

15. The method as claimed in claim 14, wherein the test card assembly comprises a substrate having at least a portion thereof made of porous materials.

16. The method as claimed in claim 15, wherein the base plate of the test card assembly includes pores with diameters approximately in a range of about 0.1 μ

m to about 10 μ

m.

17. The method as claimed in claim 10, wherein the predetermined frequency is 10 KHz.

18. The method as claimed in claim 10, wherein the predetermined frequency is 50 KHz.

19. A method for measuring hematocrit (HCT) and/or prothrombin time (PT) of a blood sample, comprising:

coupling a test card having a substantially porous surface on the substrate at a sample region of the test card to a sensor unit programmed to measure HCT and/or PT of a blood sample;

providing a blood sample to be analyzed to the test card sample region;

providing an alternating current with a predetermined frequency and voltage to the test card;

sensing a response signal from the sample on the test card;

performing a reactance analysis of the sample;

determining a phase change related to the capacitance in the blood sample using a microprocessor programmed to determine the phase change caused due to reactance in the blood sample;

determining the HCT and/or PT of the bloods sample with the microprocessor; and

providing an inspected result to a display unit of the sensor unit.

20. The method as claimed in claim 19, wherein the method further comprises the steps of:

interpolating at least one HCT value using stored PT values in a memory of the sensor unit.