Hierarchically mesostructured porous TiO₂ hollow nanofibers for high performance glucose biosensing

Effective immobilization of enzymes on an electrode surface is of great importance for biosensor development, but it still remains challenging because enzymes tend to denaturation and/or form close-packed structures. In this work, a free-standing TiO₂ hollow nanofibers (HNF-TiO₂) was successfully prepared by a simple and scalable electrospun nanofiber film template-assisted sol-gel method, and was further explored for glucose oxidase (GOD) immobilization and biosensing. This porous and nanotubular HNF-TiO₂ provides a well-defined hierarchical nanostructure for GOD loading, and the fine TiO₂ nanocrystals facilitate direct electron transfer from GOD to the electrode, also the strong interaction between GOD and HNF-TiO₂ greatly enhances the stability of the biosensor. The as-prepared glucose biosensors show good sensing performances both in O₂-free and O₂-containing conditions with good sensitivity, satisfactory selectivity, long-term stability and sound reliability. The novel textile formation, porous and hierarchically mesostructured nature of HNF-TiO₂ with excellent analytical performances make it a superior platform for the construction of high-performance glucose biosensors.