Device for performing a diagnostic test and methods for use thereof
Assay cassettes and testing devices that can be used to provide rapid, accurate, affordable, laboratory-quality testing at the point of care. Such assay cassettes and testing devices are designed to provide rapid, quantitative test results in a point-of-care setting or the like. Likewise, such assay cassettes and testing devices may eliminate or replace expensive, centralized clinical testing equipment and technical personnel. Such testing device may include automated data reporting and decision support. Methods for performing point of care diagnostic tests are also disclosed.
1. A diagnostic test system for performing a point of care diagnostic test for detecting and quantifying at least one analyte in a biological sample, comprising:
a lateral-flow chromatographic assay cassette that includes: a capture ligand capable of capturing and localizing at least one analyte of interest in a sample on an analysis surface of the lateral-flow chromatographic assay cassette, at least one reporter for visualizing the interaction of the analyte of interest and the capture ligand, and an assembly for providing an at least a two-point calibration curve for quantification of the at least one analyte of interest;
a testing device comprising
a handheld computing device selected from the group consisting of a handheld digital camera device, a cellular phone, a smart phone, and a tablet computer;
a testing apparatus configured to be coupled to the handheld computing device and configured to position the lateral-flow chromatographic assay cassette in proximity to a detector and a light source to control focal length from the detector to the lateral-flow chromatographic assay cassette and to control illumination of the lateral-flow chromatographic assay cassette by the light source, wherein the testing apparatus comprises an assay cover including a manual or electromechanical device configured to allow the angle of the lateral flow assay cassette to be adjusted relative to the light source to sample a number of angles while the handheld computing device collects data to determine the optimum angle for detection;
the light source being capable of transmitting at least one wavelength of light configured to yield a detectable signal from the at least one reporter;
a detector positioned to capture the detectable signal from the at least one reporter;
a collimating lens interposed between the detector, and the analysis surface of the lateral-flow chromatographic assay cassette; and
an interpretive algorithm stored in a computer readable format and electronically coupled to the testing device, wherein the interpretive algorithm is configured to (i) calculate a calibration curve and then (ii) convert the detectable signal from the at least one reporter to a numerical value related to the presence or amount of the at least one analyte present in a sample,
wherein the assembly for providing an at least a two-point calibration curve includes at least one of:
a lateral-flow chromatographic assay cassette that includes at least a first calibration standard and a second calibration standard configured to provide at least a two-point calibration curve, or
a lateral-flow chromatographic assay cassette that includes a test strip and a separate calibration strip cassette, wherein the calibration strip includes a capture ligand configured to capture a known amount of the analyte of interest.
2. The diagnostic test system of claim 1 , wherein the testing apparatus is physically coupled to the testing device.
3. The diagnostic test system of claim 2 , wherein the testing apparatus includes at least one indexing feature configured to align the testing apparatus with the testing device.
4. The diagnostic test system of claim 2 , wherein the testing apparatus includes one or more seals to create a light-tight environment between the testing device and the testing apparatus and between the testing apparatus and the lateral-flow chromatographic assay cassette.
5. The diagnostic test system of claim 1 , wherein the light source is at least one of a camera flash, an autofocus illuminator, ambient light, sunlight, an LED light, an incandescent lamp, or a gas-discharge lamp.
6. The diagnostic test system of claim 5 , wherein at least one focusing lens is interposed between the light source, the detector, and the analysis surface of the lateral-flow chromatographic assay cassette.
7. The diagnostic test system of claim 5 , wherein at least one wavelength filter is interposed between the light source and the analysis surface of the lateral-flow chromatographic assay cassette.
8. The diagnostic test system of claim 5 , wherein at least one light conducting fiber is interposed between the light source and the analysis surface of the lateral-flow chromatographic assay cassette.
9. The diagnostic test system of claim 1 , wherein the at least one reporter includes at least one of colored beads, colloidal gold, colloidal silver, dyes, fluorescent dyes, an electrochemical detector, a conductivity detector, or quantum dots.
10. The diagnostic test system of claim 1 , wherein the detectable signal includes at least one of emission, reflectance, diffuse scattering, elastic light scattering, transmission, fluorescence, surface plasmon detection, or Rayleigh scattering.
11. The diagnostic test system of claim 1 , the lateral-flow chromatographic assay cassette further including a tracking feature readable by the at least one of the testing device or the testing apparatus, wherein the tracking feature provides values calculating the calibration curve.
12. The diagnostic test system of claim 1 , the lateral-flow chromatographic assay cassette further including a first mechanical interlock feature configured to interlock with a corresponding second mechanical interlock feature on the testing apparatus.
13. The diagnostic test system of claim 12 , wherein the first and second mechanical interlock features are configured to align the lateral-flow chromatographic assay cassette relative to the testing apparatus, the light source, and the detector.
14. The diagnostic test system of claim 12 , wherein the first and second mechanical interlock features are configured to disable the diagnostic test system if the first and second mechanical interlock features do not align when the lateral-flow chromatographic assay cassette is inserted into the testing apparatus.
15. The diagnostic test system of claim 1 , the testing apparatus further including a target device capable of being illuminated by the light source and viewable by the detector, wherein the target device is configured for normalizing and/or calibrating the light source and the detector.
16. The diagnostic test system of claim 1 , wherein the testing apparatus is physically separate from the testing device, and wherein the testing device communicates with the testing apparatus via at least one of a wired connection or a wireless communication apparatus.