AN OPTICAL BIOSENSOR USING A FLUORESCENT, SWELLING SENSING ELEMENT

An optical sensor based on coupling the swelling of a polymer gel to a change in fluorescence intensity is discussed. A fluorophore, an amine functional group and the enzyme glucose oxidase were each incorporated into a crosslinked polymer gel, which was formed on the end of a fiber optic rod. While the amount of fluorophore remains constant, the gel volume changes in response to a change in the ionization state of the amine moiety. This change is related to glucose concentration. These effects were examined along with subsequent changes in the fluorescence of the gel.