SYSTEMS AND METHODS OF BACTERIAL GROWTH DETECTION USING DUAL LIGHT EXCITATION

A method of determining the presence of an analyte of interest in a blood sample within a test device including a sensor in aqueous media includes transmitting light to the test device at a first excitation wavelength at which light absorption of the sensor remains substantially constant as pH of the aqueous media changes, measuring an intensity of a first fluorescence signal emitted from the sensor in the test device in response to the first excitation wavelength, transmitting light to the test device at a second excitation wavelength, the second excitation wavelength being different from the first excitation wavelength, measuring an intensity of a second fluorescence signal emitted from the sensor in the test device in response to the second excitation wavelength, and normalizing, with the first fluorescence signal, the intensity of the second fluorescence signal emitted from the test device in response to the second excitation wavelength.