Accurate colorimetric based test strip reader system

A device, comprising:

• a processor, connected to a memory, the processor being configured to perform:
• illuminating a test strip wetted with a sample with select spectrums of light, wherein the test strip comprises test pads that are configured to change color in the presence of an analyte in the sample;
• obtaining at least one digital image of the test strip;
• creating calibration curves by obtaining at least one digital image of calibration pads and of test strips wetted with a series of analyte solutions having known pH at various analyte concentrations, wherein the calibration pads have color reference patches that make up a series scale of colors of known chromaticity, adjusting the color intensity from the at least one digital image of the test strips using a normalization factor, and plotting the color intensity from the at least one digital image of the test strips against the various analyte concentrations to form the calibration curves;
• and
• analyzing color intensity from the at least one digital image against the calibration curves to determine an analyte concentration in the sample with correction for one or more interference substances in the sample that change the color intensity and that, unless corrected for, affect measurement of the analyte concentration,
• wherein the processor is further configured to perform:
• learning color intensity values for the analyte in the presence of the one or more interference substances using analyte solutions with known analyte concentrations to which the one or more interference substances have been added in order to correct for the one or more interference substances in the sample.