Conductive and Highly Catalytic Nanocage for Assembly and Improving Function of Enzyme

Abstract

A conductive nanocage composed of PdNPs-doped (PdNPs = palladium nanoparticles) mesocellular carbon−silica foam was prepared using a designed wet chemical process followed by electrochemical reduction. This nanocage possessed a 3-D interconnected bottleneck mesostructure with large surface area, narrow and controllable pore-size distribution, good biocompatibility, and favorable conductivity and hydrophilicity. The produced PdNPs dispersed homogeneously on the mesowalls and provided the nanocage with a high degree of catalytic ability for the electrooxidation of hydrogen peroxide at an extremely low overpotential, and they offer the possibility to selectively detect oxidase substrates. The nanocage was size-controllable and could be used for volume-selective entrapment of enzymes without aggregation and a change of structure, which preserved good bioactivity of the entrapped enzyme and produced a highly sensitive biosensor with excellent operational and storage stability. Using glucose oxidase as a model,...