Calibration system for use with lateral flow assay test strips

• US 8,101,415 B2
• Filed: 07/05/2005
• Issued: 01/24/2012
• Est. Priority Date: 07/05/2005
• Status: Expired due to Fees

• Current Assignee: Polymer Technology Systems Incorporated (Sinocare, Inc.)
• Original Assignee: Bayer Healthcare LLC (Bayer AG)
• Inventors: Irvin, Benjamin R.
• Primary Examiner(s): Menon, Krishnan S
• Assistant Examiner(s): Fritchman, Rebecca M
• Application Number:
  US11/175,554
• Publication Number:
  US 20070010022A1
• Time in Patent Office: 2,394 Days
• Field of Search: 436/80, 436/95, 422/82.05, 422/404
• US Class Current: 436/80
• CPC Class Codes: G01N 33/54388 based on lateral flow
• CPC Class Codes: G01N 33/558 using diffusion or migration of antigen or antibody immunochromatographic test strips G01N33/54387
• CPC Class Codes: Y10T 436/144444 Glucose

Abstract

A method of adjusting a final signal value measured on a lateral flow assay test strip, by: identifying a pre-determined calibration method for the test strip, wherein the pre-determined calibration method corresponds to the manufacturing lot from which the test strip has been made; measuring signal values while performing a lateral flow assay reaction on a test strip; determining a final signal value; and adjusting the final signal value based upon the identified pre-selected calibration method for the test strip.

Claims

1. A method of adjusting a final reflectance signal value measured on a lateral flow assay test strip, comprising:

measuring a series of reflectance signal values at a test site while performing a lateral flow assay reaction on a test strip;

determining an extreme reflectance signal value representing the minimum reflectance signal value at the test site;

determining an interim reflectance signal value, wherein the interim reflectance signal value is measured at the test site a pre-determined time period after the extreme reflectance signal value is measured;

determining a final reflectance signal value at the test site after the interim reflectance signal value is determined;

pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made;

adjusting the final reflectance signal value based upon the interim reflectance signal value and the pre-determined relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made;

wherein the step of adjusting the final reflectance signal value is conducted after the step of determining a final reflectance signal value.

2. The method of claim 1, wherein the pre-determined time period is pre-determined for the manufacturing lot from which the test strip has been made.

3. The method of claim 1, wherein pre-determining the relationship between the interim reflectance signal value and the final reflectance signal value for a plurality of test strips from the manufacturing lot from which the test strip has been made comprises:

determining the relationship between the interim signal value and the final signal value for an exemplary test strip from the manufacturing lot from which the test strip has been made.

4. The method of claim 1, further comprising:

determining the time at which the extreme reflectance signal value is measured, wherein the pre-determined time period after the extreme reflectance signal value has been measured is a function of the time at which the extreme reflectance signal value is measured for the manufacturing lot from which the test strip has been made.

5. The method of claim 4, wherein adjusting the final reflectance signal value based upon the interim reflectance signal value comprises:

pre-determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for the plurality of test strips from the same manufacturing lot;

pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the plurality of test strips from the same manufacturing lot; and

adjusting the final reflectance signal value based upon the pre-determined relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made.

6. The method of claim 5, wherein pre-determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for the plurality of test strips from the same manufacturing lot comprises:

determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for an exemplary test strip from the manufacturing lot from which the test strip has been made.

7. The method of claim 5, wherein pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the plurality of test strips from the same manufacturing lot comprises:

determining a relationship between the interim reflectance signal value and the final reflectance signal value for an exemplary test strip from the manufacturing lot from which the test strip has been made.

8. The method of claim 1, further comprising:

determining a second interim reflectance signal value, wherein the second interim reflectance signal value is measured a second pre-determined time period after the extreme reflectance signal value is measured; and

adjusting the final reflectance signal value based upon both the interim signal value and the second interim reflectance signal value.

9. The method of claim 8, wherein adjusting the final reflectance signal value based upon both the interim reflectance signal value and the second interim reflectance signal value comprises:

pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made;

pre-determining a relationship between the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made; and

adjusting the final reflectance signal value based upon the pre-determined relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made.

10. The method of claim 9, wherein pre-determining the relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the test strip has been made comprises:

determining the relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for an exemplary test strip from the manufacturing lot from which the test strip has been made.

11. The method of claim 1, wherein the steps of determining an extreme reflectance signal value and determining a final reflectance signal value are by measuring.

12. The method of claim 1, wherein the final reflectance signal value is obtained at a second predetermined time.

13. A method of adjusting a final reflectance signal value measured on a lateral flow assay test strip, comprising:

measuring a series of reflectance signal values at a test site while performing a lateral flow assay reaction on a first test strip;

determining an extreme reflectance signal value representing the minimum reflectance signal value at the test site;

determining an interim reflectance signal value, wherein the interim reflectance signal value is measured at the test site a pre-determined time period after the extreme reflectance signal value is measured;

determining a final reflectance signal value at the test site after the interim reflectance signal value is determined;

utilizing a known relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made, exclusive of the first test strip;

adjusting the final reflectance signal value based upon the interim reflectance signal value and the pre-determined relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made.

14. The method of claim 13, wherein the steps of determining an extreme reflectance signal value and determining a final reflectance signal value are by measuring.

15. The method of claim 13, wherein the time period is pre-determined for the manufacturing lot from which the test strip has been made.

16. The method of claim 13, wherein utilizing a known relationship between the interim reflectance signal value and the final reflectance signal value for a plurality of test strips from the manufacturing lot from which the first test strip has been made comprises:

determining the relationship between the interim signal value and the final signal value for an exemplary test strip from the manufacturing lot from which the first test strip has been made.

17. The method of claim 13, further comprising:

determining the time at which the extreme reflectance signal value is measured, wherein the pre-determined time period after the extreme reflectance signal value has been measured is a function of the time at which the extreme reflectance signal value is measured for the manufacturing lot from which the first test strip has been made.

18. The method of claim 17, wherein adjusting the final reflectance signal value based upon the interim reflectance signal value comprises:

pre-determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for the plurality of test strips from the same manufacturing lot;

pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the plurality of test strips from the same manufacturing lot; and

adjusting the final reflectance signal value based upon the pre-determined relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made.

19. The method of claim 18, wherein pre-determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for the plurality of test strips from the same manufacturing lot comprises:

determining a relationship between the time at which the extreme reflectance signal value is measured and the time at which the interim reflectance signal value is measured for an exemplary test strip from the manufacturing lot from which the first test strip has been made.

20. The method of claim 18, wherein pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the plurality of test strips from the same manufacturing lot comprises:

determining a relationship between the interim reflectance signal value and the final reflectance signal value for an exemplary test strip from the manufacturing lot from which the first test strip has been made.

21. The method of claim 13, further comprising:

determining a second interim reflectance signal value, wherein the second interim reflectance signal value is measured a second pre-determined time period after the extreme reflectance signal value is measured; and

adjusting the final reflectance signal value based upon both the interim signal value and the second interim reflectance signal value.

22. The method of claim 21, wherein adjusting the final reflectance signal value based upon both the interim reflectance signal value and the second interim reflectance signal value comprises:

pre-determining a relationship between the interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made;

pre-determining a relationship between the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made; and

adjusting the final reflectance signal value based upon the pre-determined relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made.

23. The method of claim 22, wherein pre-determining the relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for the manufacturing lot from which the first test strip has been made comprises:

determining the relationships between the interim reflectance signal value and the final reflectance signal value and the second interim reflectance signal value and the final reflectance signal value for an exemplary test strip from the manufacturing lot from which the first test strip has been made.

24. The method of claim 13, wherein the step of adjusting the final reflectance signal valve is conducted after the step of determining a final reflectance signal value.