Methods and systems for calibrating illumination source of diagnostic test system

• US 10,191,043 B2
• Filed: 10/18/2016
• Issued: 01/29/2019
• Est. Priority Date: 04/22/2005
• Status: Active Grant

• Current Assignee: Alverix, Inc. (Becton, Dickinson & Co)
• Original Assignee: Alverix, Inc. (Becton, Dickinson & Co)
• Inventors: Petruno, Patrick T., Petrilla, John F., Brosnan, Michael J., Zhou, Rong, Roitman, Daniel B., Curry, Bo U.
• Primary Examiner(s): Merkling, Sally A
• Application Number:
  US15/296,872
• Publication Number:
  US 20170199183A1
• Time in Patent Office: 833 Days
• CPC Class Codes: G01N 2021/6439 with indicators, stains, dyes, tags, labels, marks
• CPC Class Codes: G01N 21/17 Systems in which incident light is modified in accordance with the properties of the material investigated where the material investigated is optically excited causing a change in wavelength of the incident light G01N21/63
• CPC Class Codes: G01N 21/274 Calibration, base line adjustment, drift correction
• CPC Class Codes: G01N 21/6428 Measuring fluorescence of fluorescent products of reactions or of fluorochrome labelled reactive substances, e.g. measuring quenching effects, using measuring "optrodes" in vivo A61B5/00; immunoassay G01N33/53
• CPC Class Codes: G01N 21/8483 Investigating reagent band test-element handling not specific to a test method G01N33/4875; analytical elements specific to chemical analysis of biological material G01N33/52; autometer with reagent band G01N35/04
• CPC Class Codes: G01N 2201/062 LED's
• CPC Class Codes: G01N 2201/067 Electro-optic, magneto-optic, acousto-optic 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: G01N 33/58 involving labelled substances G01N33/53 takes precedence
• CPC Class Codes: Y10S 435/805 Test papers
• CPC Class Codes: Y10S 435/823 Acetobacter
• CPC Class Codes: Y10S 436/807 Apparatus included in process claim, e.g. physical support structures
• CPC Class Codes: Y10S 436/809 Multifield plates or multicontainer arrays
• CPC Class Codes: Y10S 436/81 Tube, bottle, or dipstick
• CPC Class Codes: Y10S 436/823 Immunogenic carrier or carrier per se
• CPC Class Codes: Y10T 436/25125 Digestion or removing interfering materials

Abstract

An assay test strip includes a flow path, a sample receiving zone, a label, a detection zone that includes a region of interest, and at least one position marker. The at least one position marker is aligned with respect to the region of interest such that location of the at least one position marker indicates a position of the region of interest. A diagnostic test system includes a reader that obtains light intensity measurement from exposed regions of the test strip, and a data analyzer that performs at least one of (a) identifying ones of the light intensity measurements obtained from the test region based on at least one measurement obtained from the at least one reference feature, and (b) generating a control signal modifying at least one operational parameter of the reader based on at least one measurement obtained from the at least one reference feature.

Claims

1. A diagnostic test system, comprising:

a test strip that comprises a flow path for a fluid sample, a sample receiving zone coupled to the flow path, a label that specifically binds a target analyte, a detection zone coupled to the flow path and comprising a test region exposed for optical inspection and having an immobilized test reagent that specifically binds the target analyte, and at least one reference feature comprising an illumination source calibration region;

a reader comprising an illumination source operable to illuminate the test strip when the test strip is loaded in a port for receiving the test strip, the reader further comprising a detection system that is configured to obtain light intensity measurements from exposed regions of the test strip when the test strip is loaded in the port; and

a data analyzer comprising software configured to

process the light intensity measurements obtained by the reader,

determine an illumination source output measure from at least one light intensity measurement obtained from the illumination source calibration region,

generate a control signal calibrating the illumination source based on a comparison of the determined illumination source output measure to a reference value, and

adjust a light intensity output of the illumination source when the determined illumination source output measure is different than the reference value.

2. The system of claim 1, wherein the control signal is configured to calibrate one or more operational parameters of the illumination source based on at least one light intensity measurement obtained from the illumination source calibration region.

3. The system of claim 1, wherein the at least one reference feature comprises a first illumination source calibration region and a second illumination source calibration region.

4. The system of claim 3, wherein the first illumination source calibration region and the second illumination source calibration region have a reflection or an emission that is greater than a reflection or an emission of an adjacent region of the test strip with respect to light within a target wavelength range.

5. The system of claim 3, wherein the first illumination source calibration region and the second illumination source calibration region reflect greater than 90% of light within a target wavelength range of about 390 nm to about 770 nm.

6. The system of claim 3, wherein the first illumination source calibration region and the second illumination source calibration region comprise a film of metal.

7. The system of claim 3, wherein the first illumination source calibration region and the second illumination source calibration region comprise immobilized fluorescent particles.

8. The system of claim 3, wherein the first illumination source calibration region and the second illumination source calibration region comprise a different surface profiles on the test strip than adjacent areas of the test strip.

9. The system of claim 1, wherein the illumination source output measure comprises a peak intensity value or an average intensity value computed from the at least one light intensity measurement.

10. The system of claim 1, wherein the data analyzer comprises software configured to generate the control signal based on the determined illumination source output measure.

11. The system of claim 1, wherein the data analyzer comprises software configured to increase the light intensity output of the illumination source when the determined illumination source output measure is less than the reference value.

12. The system of claim 1, wherein the data analyzer comprises software configured to decrease the light intensity output of the illumination source when the determined illumination source output measure is greater than the reference value.

13. The system of claim 1, wherein the data analyzer comprises software that is configured to iteratively generate control signals until the determined illumination source output measure is within a specified range of the reference value.

14. The system of claim 3, wherein the first illumination source calibration region is located upstream of the test region and the second illumination source calibration region is located downstream of the test region, and wherein the data analyzer comprises software configured to determine a first illumination source output measure from at least one light intensity measurement obtained from the first illumination source calibration region and a second illumination output measure from at least one light intensity measurement obtained from the second illumination source calibration region.

15. The system of claim 14, wherein the first illumination source output measure is different than the second illumination source output measure.

16. The system of claim 15, wherein the data analyzer comprises software configured to detect variations in the output of the illumination source across the detection zone based on the difference between the first illumination source output measure and the second illumination source output measure.

17. The system of claim 15, wherein the data analyzer comprises software configured to scale light intensity measurements obtained from the test region and a control region based on the difference between the first illumination source output measure and the second illumination source output measure.

18. The system of claim 17, wherein the amount the data analyzer scales the light intensity measurements is obtained from a lookup table or a parametric curve.