A unique, two-component sensing system for fluorescence detection of glucose and other carbohydrates*

In our glucose-sensing system, a boronic acid-modified viologen molecule quenches the fluorescence of a separate dye molecule. When glucose or other mono - saccharides are added and bind to the boronic acid, the quenching ability of the viologen is diminished and fluorescence increases. Thus, changes in the fluorescence of the dye can be correlated with changing glucose concentration. Quenching and sugar-sensing results are explained by an electrostatic interaction between dye and quencher. This modular system can be configured in a nearly unlimited number of ways through substitution and multiplexing of the two fundamental quencher and dye components. Significantly, fluorescent quantum dots (QDs) can also be used as the reporter component. The system can also be immobilized in a hydrogel polymer to provide real-time, reversible sugar sensing.