Two-dimensional hybrid mesoporous Fe2O3-graphene nanostructures: a highly active and reusable peroxidase mimetic toward rapid, highly sensitive optical detection of glucose.

In this article, for the first time, two-dimensional hybrid mesoporous Fe2O3-graphene (mFe2O3-G) nanostructures were developed as a peroxidase mimetic with catalytic activities superior to those of mFe2O3, G, and previously reported Fe-based peroxidase mimetics. The high-surface-area mFe2O3 not only offers a large number of catalytically active sites, but also facilitates the diffusion of 3,3,5,5-tetramethylbenzidine (TMB) and H2O2 toward G surface. On the other hand, G is π-rich and thus favors the adsorption and enrichment of TMB within these pores. These synergistic effects lead to highly improved catalytic performances. Based on these findings, a simple, rapid, and highly sensitive and selective optical detector of glucose has been developed and demonstrated in buffer solution with a pretty low detection limit of 0.5 μM. In addition, this nanosensor is reusable and can also be used for glucose detection in diluted serum.