Method and apparatus for performing a lateral flow assay

• US 7,297,529 B2
• Filed: 08/04/2003
• Issued: 11/20/2007
• Est. Priority Date: 11/23/1998
• Status: Expired due to Fees

• Current Assignee: Relia Biotechnologies (Shenzhen) Ltd.
• Original Assignee: Relia Diagnostic Systems Inc.
• Inventors: Sierra, George H., Polito, Alan J., Phillips, Alan, Thayer, Richard M., Nixon, Dennis, Neubarth, Stuart, DiNello, Robert K.
• Primary Examiner(s): Siew; Jeffrey
• Assistant Examiner(s): HINES, JANA A
• Application Number:
  US10/634,331
• Publication Number:
  US 20050074899A1
• Time in Patent Office: 1,569 Days
• Field of Search: 435/283.1, 435/285.2, 435/286.1, 435/287.2, 435/287.3, 29/38, 292/44, 123/406.11, 123/406.66, 123/407, 318/662, 356/38, 356/244, 388/919, 429/22, 429/23, 429/26, 429/61, 429/62, 429/90, 438/171, 505/192
• US Class Current: 435/285.2
• 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 useful for detecting the addition of a sample to a test strip in a lateral flow assay comprising:

a housing having a receptacle for retaining a test strip for a lateral flow assay; and

an autostart means;

wherein the autostart means comprises a capacitance sensor that senses a change in capacitance when a sample or buffer is applied to the test strip in the receptacle, and initiates timing of the assay, and a means for regulating voltage across the capacitance sensor.

2. The apparatus of claim 1, further comprising a heating element positioned to lie under and contact the test strip when the test strip is in place.

3. The apparatus of claim 1, further comprising a test strip.

4. The apparatus of claim 3, wherein the test strip contains a biological sample.

5. The apparatus of claim 4, wherein the biological sample is selected from the group consisting of whole blood, serum, plasma, and urine.

6. The apparatus of claim 4, wherein the biological sample is a human biological sample.

7. The apparatus of claim 4, wherein the biological sample is a non-human biological sample.

8. The apparatus of claim 7, wherein the non-human biological sample is a sample consisting of a livestock and a food product.

9. The apparatus of claim 1, further comprising an optical sensor aligned with the test strip in the receptacle.

10. The apparatus of claim 9 further comprising a moving mechanism attached to the optical sensor that moves the optical sensor with respect to the test strip.

11. The apparatus of claim 9 further comprising a moving mechanism attached to the housing that moves the test strip with respect to the optical sensor, wherein the housing is a cartridge.

12. The apparatus of claim 1, further comprising a sensor that detects the insertion of the housing, wherein the housing is a cartridge.

13. The apparatus of claim 12, wherein the sensor is an infrared sensor.