Method and material for ratiometric fluorescent determination of analyte concentration.

Abstract

Optical sensors are used to measure the concn. of oxygen or other analytes in a sample. The ratiometric method uses an indicator dye which is pyranthrene, flavanthrene or a suitable deriv. dispersed or immobilized in an analyte permeable matrix. The matrix is excited with light at one or more wavelengths, or fluorescence emissions of the indicator are measured at one or more wavelengths, or both excitation and emission are performed and measured at multiple wavelengths. These indicator dyes exhibit different sensitivity to quenching by the analyte at different excitation wavelengths and also at different emission wavelengths. Each emission resulting from a different excitation is divided by the measured intensity of its excitation to compensate for illumination variations. The ratio of the resulting signals for each excitation is then used for detg. the analyte concn. Alternatively, the ratio of emissions at a single excitation wavelength are used in a similar manner. [on SciFinder(R)]