Laccase biosensor fabricated on flower-shaped yolk-shell SiO2 nanospheres for catechol detection

In this study, we developed a facile one-pot strategy for fabricating flower-shaped yolk-shell SiO2 nanospheres (FYSSns) using cetyltrimethylammonium bromide-polyvinylpyrrolidone-cyclohexane-ethanol-water vesicle-microemulsion composite aggregation as templates through a simple solvothermal route. FYSSns displayed yolk-shell structures with flower-shaped yolks (260-320 nm) with ordered radial mesochannels (similar to 7 nm), large cavities (100-120 nm), and thin silica shells (20-30 nm). High laccase immobilization amounts were achieved using FYSSns as supporter, and the laccase-modified FYSSns were applied to the electrochemical sensor with high selectivity for detecting catechol. Under the optimized conditions, the proposed sensor showed a wide linear range from 12.5-450 mu M over catechol concentration and a low detection limit of 1.6 mu M. The outstanding performance was attributed to the advantages of FYSSns, such as large specific surface area and its own mesochannel structure.