The authors use glucose-binding protein (GBP) to mech. actuate a fluorescent single-walled carbon nanotube (SWNT), resulting in reversible exciton quenching in response to glucose. The GBP is covalently conjugated with carboxylated poly(vinyl alc.)-wrapped SWNTs (cPVA/SWNTs), which leads to allosterically controlled optical transduction in response to glucose. Carboxy groups on the cPVA/SWNT complex were used to attach the protein, through amine coupling to lysine residues on the GBP. These complexes demonstrate a reversible fluorescence quenching in response to glucose. The hypothesis is that the hinge bending action assocd. with glucose recognition modulates the fluorescence of the SWNT. The system can be used as a glucose biosensor. [on SciFinder(R)]