Agglutination Based Sample Testing Device

• US 20110136257A1
• Filed: 06/11/2010
• Published: 06/09/2011
• Est. Priority Date: 03/18/2003
• Status: Active Grant

• Current Assignee: Platform Diagnostics Limited
• Original Assignee: Platform Diagnostics Limited
• Inventors: BOND, Damian Joseph Peter, MINTER, Timothy John, MINTER, Stephen John
• Granted Patent: US 8,283,182 B2
• Time in Patent Office: Days
• US Class Current: 436/501
• CPC Class Codes: G01N 2333/59 Follicle-stimulating hormone [FSH]; Chorionic gonadotropins, e.g. HCG; Luteinising hormone [LH]; Thyroid-stimulating hormone [TSH]
• CPC Class Codes: G01N 33/5304 Reaction vessels, e.g. agglutination plates for solid-phase systems G01N33/543
• CPC Class Codes: G01N 33/54366 Apparatus specially adapted for solid-phase testing

Abstract

A sample testing device for testing for the presence of a component of interest in a liquid sample comprises: (a) at least one capillary pathway which has an upstream end and a downstream end and which incorporates a reagent system capable of causing agglutination with said component to be detected (the test capillary); (b) preferably, but optionally, at least one capillary pathway having an upstream end and a downstream end (the control capillary); (c) a sampling region to which the liquid sample is applied and from which the sample is able to enter the upstream ends of the test capillary(s) and if present the control capillary(s); (d) a power source; (c) detection arrangements electrically associated with said power source for detecting the presence of liquid at a downstream region of said testing capillary(s) and if present the control capillary(s); (f) display means operated by said power source for indicating the result of the test; and (g) signal processing means associated with the power source, detection arrangement and display means for evaluating the result of the test and providing said result on the display means. The device may be used for a pregnancy test, more particularly for determining the presence of hCG in urine.

Claims

1. A method for testing for the presence of a component of interest in a liquid sample, comprising:

(a) providing a sample testing device, wherein the device comprises;

(i) at least one test capillary which has an upstream end and a downstream end and which incorporates an agglutination reagent system capable of causing agglutination with the component of interest;

(ii) a sampling region for receiving the liquid sample and from which the liquid sample enters the upstream end of the test capillary;

(iii) a power source;

(iv) a detector electrically associated with the power source for detecting presence of the liquid sample at a downstream region of the test capillary;

(v) a display device operated by the power source for indicating a result of the test; and

(vi) a signal processing means associated with the power source, detector and display device for evaluating the result of the test and providing the result on the display device;

(b) applying the liquid sample to the sampling region; and

(c) detecting the presence or absence of the liquid sample at the downstream region of the test capillary at a pre-determined time interval,

wherein absence of the liquid sample at the downstream region of the test capillary at the pre-determined time interval is indicative of the presence of the component.

2. The method of claim 1, wherein measurement of the pre-determined time interval commences upon application of the liquid sample to the sampling region.

3. The method of claim 1, wherein the signal processing means comprises a timer for measuring the pre-determined time interval.

4. The method of claim 1, wherein the sample testing device further comprises at least one control capillary having an upstream end and a downstream end, wherein the liquid sample enters the upstream end of the control capillary from the sampling region, and wherein the method further comprises detecting the presence or absence of the liquid sample at a downstream region of the control capillary at the pre-determined time interval.

5. The method of claim 4, wherein the presence of the liquid sample at the downstream region of the control capillary at the pre-determined time interval confirms that the sample testing device is functioning normally.

6. The method of claim 4, wherein the control capillary comprises a non-agglutinating reagent system.

7. The method of claim 1, wherein the power source comprises electrodes of dissimilar metals provided at the sampling region of the sample test device, the electrodes being adapted to generate a current when the liquid sample is applied to the sampling region.

8. The method of claim 7, wherein the electrodes of the dissimilar metals alternate with each other.

9. The method of claim 1, wherein the agglutination reagent system comprises beads on which is immobilized a binding partner for the component of interest.

10. The method of claim 9, wherein the binding partner is an antibody.

11. The method of claim 1, wherein the agglutination reagent system comprises a binding partner for the component of interest immobilized on walls of the test capillary.

12. The method of claim 11, wherein the binding partner is an antibody.

13. The method of claim 1, wherein the component of interest is human Chorionic Gonadotropin (hCG).

14. The method of claim 1, wherein the test capillary is formed by a co-operating plate and lid arrangement, the plate being formed with channels which become capillary tubes on location of the lid.

15. The method of claim 1, wherein the downstream region of the test capillary has at least one aperture and the detector is provided beneath the aperture.

16. The method of claim 1, wherein the detector comprises a pair of electrodes across which a potential difference is applied.

17. The method of claim 1, wherein the test capillary includes a particulate material to enhance the change in flow rate.

18. The method of claim 17, wherein the particulate material is an inert material.

19. The method of claim 18, wherein the inert particulate material is silica or bentonite.

20. The method of claim 17, wherein said particulate material is a swellable polymer.