METHOD AND APPARATUS FOR PERFORMING A LATERAL FLOW ASSAY

• US 20080031779A1
• Filed: 10/08/2007
• Published: 02/07/2008
• Est. Priority Date: 11/23/1998
• Status: Active Grant

• Current Assignee: Relia Biotechnologies (Shenzhen) Ltd.
• Original Assignee: Relia Diagnostic Systems Inc.
• Inventors: Phillips, Alan, Polito, Alan, Sierra, George, Nixon, Dennis, Thayer, Richard, DiNello, Robert, Neubarth, Stuart
• Granted Patent: US 8,354,270 B2
• Time in Patent Office: Days
• US Class Current: 422/68.1
• CPC Class Codes: B01L 3/5023 with a sample being transported to, and subsequently stored in an absorbent for analysis
• CPC Class Codes: G01N 27/227 Sensors changing capacitance upon adsorption or absorption of fluid components, e.g. electrolyte-insulator-semiconductor sensors, MOS capacitors G01N27/225 takes precedence
• CPC Class Codes: G01N 33/4875 Details of handling test elements, e.g. dispensing or storage, not specific to a particular test method test-elements per se B01L, automatic analysers G01N35/00, in-vivo analysis on the human body for medical diagnosis A61B
• CPC Class Codes: G01N 33/54386 Analytical elements
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/54393 Improving reaction conditions or stability, e.g. by coating or irradiation of surface, by reduction of non-specific binding, by promotion of specific binding
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10S 436/806 Electrical property or magnetic property
• CPC Class Codes: Y10S 436/807 Apparatus included in process claim, e.g. physical support structures
• CPC Class Codes: Y10T 436/114998 with treatment or replacement of aspirator element [e.g., cleaning, etc.]

Abstract

An embodiment of the present invention provides a method for performing a lateral flow assay. The method includes depositing a sample on a test strip at an application region, detecting a first detection signal arising from the test strip in the first detection zone, and generating a baseline for the first measurement zone by interpolating between values of the detection signal outside of the first measurement zone and inside of the first detection zone. The method may include locating a beginning boundary and an ending boundary for the first measurement zone on the test strip. Additional detection zones having measurement zones may also be incorporated with the embodiment.

Claims

1. An apparatus for conducting a lateral flow assay on a test strip for detection of an analyte in a sample comprising:

a housing having a receptacle;

an autostart means; and

a test strip comprising an internal quality control means;

wherein the receptacle retains the test strip and the autostart means senses application of sample or buffer to the test strip and initiates timing of the assay.

2. The apparatus of claim 1, wherein the internal quality control means of the test strip comprises:

a first control measurement zone including a first control agent immobilized therein which is capable of binding a control binding agent, and

a second control measurement zone including a second control agent immobilized therein which is capable of binding the control binding agent.

3. The apparatus of claim 1, further comprising a detection means for detecting a signal from the test strip.

4. The apparatus of claim 1, further comprising a heating element positioned to lie under and contact the test strip.

5. The apparatus of claim 1, wherein the detection of the analyte includes quantitation of the analyte.

6. The apparatus of claim 1, further comprising a first sensor that detects a signal emitted by the test strip.

7. The apparatus of claim 1, further comprising a processor, memory resources, and software for determining the amount of analyte in the sample.

8. The apparatus of claim 1, wherein the receptacle retains a cartridge containing the test strip.

9. The apparatus of claim 1, wherein the autostart means comprises a capacitance sensor.

10. The apparatus of claim 1, wherein the autostart means comprises a capacitance sensor and a means for regulating voltage across the capacitance sensor.

11. The apparatus of claim 1, wherein the autostart means comprises a capacitance sensor and a means for regulating voltage across the capacitance sensor, and wherein the means for regulating voltage across the capacitance sensor changes the voltage across the capacitance sensor in a periodic pattern.

12. The apparatus of claim 1, wherein the autostart means comprises a capacitance sensor and a means for regulating voltage across the capacitance sensor, and wherein the means for regulating voltage across the capacitance sensor is a current source, and a switch.

13. The apparatus of claim 1, wherein the autostart means comprises a capacitance sensor, and wherein the capacitance sensor is part of an inductor-capacitor (“

LC”

) circuit.

14. The apparatus of claim 3, wherein the signal is a reflectance, fluorescence or radiation signal.

15. The apparatus of claim 4, further comprising a temperature feedback control.

16. The apparatus of claim 6, wherein the first sensor is an optical sensor.

17. The apparatus of claim 6, wherein the receptacle retains a cartridge containing the test strip, wherein the apparatus further comprises a second sensor that detects a code on the cartridge, and wherein the second sensor is an optical sensor.

18. The apparatus of claim 8, further comprising a detector that detects insertion of the cartridge containing the test strip into the receptacle.

19. The apparatus of claim 18, wherein the detector is an infrared sensor.

20. The apparatus of claim 1, further comprising:

a heating element for locally heating the test strip;

a sensor that detects a signal emitted by the test strip; and

a processor, memory resources, and software for determining the amount of analyte in the sample,

wherein the autostart means comprises a capacitance sensor.