POMOF-derived Fe2O3@P2W18 with SWNT nanocomposites as colorimetric biosensors for glucose

Fe2O3 as artificial enzymes (nanoenzymes) was found to possess excellent peroxidase-like activities, due to the relatively high catalytic activity, low cost and good stability. To further improve the peroxidase-like activities of Fe2O3, in the work, ternary Fe2O3@P2W18@SWNT nanocomposites were successfully prepared by calcinating MIL-101(Fe)@P2W18 to obtain Fe2O3@P2W18, then loaded by single wall carbon nanotubes (SWNT), and the peroxidase-like activities were evaluated by detecting hydrogen peroxide (H2O2) and glucose (GLC). Compared with Fe2O3, P2W18 and SWNT, Fe2O3@P2W18@SWNT nanocomposites exhibit better peroxidase-like properties due to the nature of all components and the best synergistic effect. In addition, the peroxidase-like activities of Fe2O3@P2W18@SWNT nanocomposites depend largely on the doping quality of P2W18 and SWNT, and the optimized ratio of Fe2O3:P2W18:SWNT is 4:1:5. Moreover, a sensitive colorimetric detection based on Fe2O3@P2W18@SWNT-glucose oxidase (GOx)-TMB for GLC was developed with a sensitivity of 0.15 μM. The ternary Fe2O3@P2W18-2@SWNT-2 nanocomposites were successfully fabricated, and their peroxidase-like activities were evaluated. The results show that the synergistic effect can greatly improve the overall performance of ternary nanocomposites. Moreover, Moreover, a sensitive colorimetric detection based on Fe2O3@P2W18-2@SWNT-2-glucose oxidase (GOx)-TMB for GLC was developed with a sensitivity of 0.15 μM. [Display omitted] •Fe2O3 can promote the production of ·OH by hydrogen peroxide through the electron transfer of fenton-like reaction.•The introduction of P2W18 can increase the "active site" of Fe2O3.•the introduction of SWNT provides higher specific surface area and faster electron transfer rates.•Their matching and compatibility promote the performance improvement of Fe2O3@P2W18@SWNT.