QUANTIFYING COLOR CHANGES OF CHEMICAL TEST PADS INDUCED BY SPECIFIC CONCENTRATIONS OF BIOLOGICAL ANALYTES UNDER DIFFERENT LIGHTING CONDITIONS

• US 20190310203A1
• Filed: 03/09/2019
• Published: 10/10/2019
• Est. Priority Date: 08/08/2012
• Status: Active Grant

• Current Assignee: Healthy.io, Ltd.
• Original Assignee: Scanadu Incorporated
• Inventors: Burg, Bernard, Zizi, Martin, Rowe, Aaron Alexander, Smart, Anthony, De Brouwer, Walter
• Granted Patent: US 11,131,633 B2
• Time in Patent Office: Days
• CPC Class Codes: G01N 2021/7759 Dipstick; Test strip
• CPC Class Codes: G01N 21/78 producing a change of colour
• CPC Class Codes: G01N 21/79 Photometric titration
• CPC Class Codes: G01N 2201/0221 Portable; cableless; compact; hand-held
• CPC Class Codes: G01N 2201/12 Circuits of general importance; Signal processing
• CPC Class Codes: G01N 33/48 Biological material, e.g. blood, urine G01N33/02, G01N33/26, G01N33/44, G01N33/46 take precedence; Haemocytometers counting blood corpuscules distributed over a surface by scanning the surface G06M11/02

Abstract

Color quantification of chemical test pads and titration of analytes can be performed under different lighting conditions. In one embodiment, the lighting condition is estimated under which a digital image is captured and utilized to select a set of reference colors from which the quantified color is compared to determine the titration. In another embodiment, a plurality of comparisons are made with different lighting conditions with the result having the highest confidence level being selected to determine the titration.

Claims

1-24. -24.

25. A system for performing diagnostic tests of a biological sample, the system comprising:

a diagnostic instrument comprising a color reference comprising a plurality of reference samples of different colors and a plurality of test media containing a plurality of reagents, wherein the plurality of reagents change color in the presence of various levels of a plurality of different analytes in a biological sample; and

a portable electronic device comprising a digital camera sensor for capturing a digital image of at least a portion of the diagnostic instrument and a processor, wherein the processor is configured to;

identify at least one of the reference samples and at least one of the test media in the digital image of the diagnostic instrument;

determine a dominant camera-captured color of a reference sample and a dominant camera-captured color of the at least one test medium;

estimate lighting conditions under which the digital image is captured;

correct the dominant camera-captured color of the at least one test medium, in response to a color correction factor derived at least in part from the dominant camera-captured color of the reference sample, to determine a corrected test medium color; and

determine a test result including an analyte concentration of the biological sample by a comparison of the corrected test medium color to a set of possible test medium colors corresponding to predetermined analyte concentrations, wherein the set of possible test medium colors is responsive to the estimated lighting conditions under which the digital image is captured.

26. The system of claim 25, wherein the plurality of test media are arranged in a plurality of test specific sequences.

27. The system of claim 25, further comprising an identification label associated with the diagnostic instrument, wherein the digital image includes at least a portion of the identification label.

28. The system of claim 27, wherein the processor is further configured to identify the identification label and validate the diagnostic instrument in response to the identification information included on or associated with the identification label.

29. The system of claim 25, wherein the portable electronic device further comprises a data transmitter to transmit at least a portion of the test results to an external source.

30. The system of claim 25, wherein the portable electronic device further comprises a visual display device for displaying instructions for using the system or for displaying the test result.

31. A portable electronic device for analyzing a digital image of a diagnostic instrument, the portable electronic device comprising:

at least one processor;

at least one display device coupled in communication with the at least one processor;

at least one camera sensor coupled in communication with the at least one processor; and

at least one computer-readable medium coupled in communication with the at least one processor comprising program instructions that, when executed by the at least one processor, cause the portable electronic device to;

capture a digital image of at least a portion of the diagnostic instrument, which has been exposed to a biological sample, with the camera sensor, the diagnostic instrument comprising at least one color reference comprising a plurality of reference samples of different colors and at least one test medium containing a reagent, which changes color in the presence of particular analytes in the biological sample;

identify at least one of the reference samples for the at least one medium in the diagnostic instrument;

determine a dominant camera-captured color of a reference sample and a dominant camera-captured color of the at least one test medium;

estimate lighting conditions under which the digital image is captured;

correct the dominant camera-captured color of the at least one test medium, in response to a color correction factor derived at least in part from the dominant camera-captured color of the reference sample, to determine a corrected test medium color; and

determine a test result including an analyte concentration of the biological sample by a comparison of the corrected test medium color to a set of possible test medium colors corresponding to predetermined analyte concentrations, wherein the set of possible test medium colors is responsive to the estimated lighting conditions under which the digital image is captured.

32. The portable electronic device of claim 31, wherein the program instructions further cause the portable electronic device to display use instructions on the at least one display device, and wherein the use instructions explain to a user at least how to expose the diagnostic instrument to the biological sample or how to capture the digital image of the diagnostic instrument.

33. The portable electronic device of claim 32, wherein the use instructions are displayed in conjunction with a video image of the diagnostic instrument.

34. The portable electronic device of claim 31, further comprising a timer and wherein the program instructions further cause the portable electronic device to:

instruct a user to expose the diagnostic instrument to the biological sample;

measure a predetermined exposure time with the timer; and

instruct the user to capture the digital image with the camera sensor after the predetermined exposure time has been measured.

35. The portable electronic device of claim 34, wherein the program instructions further cause the portable electronic device to:

measure an actual exposure time with the timer, the actual exposure time being the time between instructing a user to expose the diagnostic instrument to the biological sample and capturing the digital image of the diagnostic instrument; and

record a corrected exposure time, wherein the corrected exposure time is based on a difference between the predetermined exposure time and the actual exposure time.

36. The portable electronic device of claim 35, wherein the program instructions further cause the portable electronic device to color correct the dominant camera-captured color of the at least one test medium based on the corrected exposure time.

37. The portable electronic device of claim 31, further comprising a data entry device, and wherein the program instructions further cause the portable electronic device to

receive patient information from the data entry device;

and

compare the test results with the patient information to determine a possible patient condition.

38-78. -78. (canceled)