Biosensor Based on TTF@SiO₂ Nanoparticles as Electron Transfer Mediator for the Determination of Glucose

Tetrathiafulvalene(TTF) was doped in an SiO₂ network and the resulting nanocomposite was used as a mediator for the selective detection of glucose. The uniform TTF-doped silica(TTF@ SiO₂) nanoparticles were prepared by the water-in-oil(W/O) microemulsion method, and were characterized by transmission electron microscopy(TEM). The core-shell structure TTF@ SiO₂ could prevent TTF from leaching out into an aqueous solution. Combined with chitosan (CHIT), which serves as a scaffold for glucose oxidase and nanocomposite immobilization, the GCE / TTF@ SiO₂-CHIT-GO_x biosensor was developed. Under optimal conditions, the biosensors exhibit a linear range of 1.0 × 10^-5 - 5 × 10^-3 mol/L with a detection limit down to 5.0 μmol/L(S / N = 3). The excellent selectivity, sensitivity, and stability of the glucose biosensor show its potential for practical applications.