Increasing enzyme-like activity by in situ anchoring of Ag3PO4 nanoparticles on keratin–inorganic hybrid nanoflowers†
Herein, we propose a strategy of rapid assembly of Ag3PO4 nanoparticles (NPs) within three dimensional (3D) keratin–inorganic hybrid nanoflowers (keratin-NF@Ag3PO4) with a facile in situ ion sedimentation approach. The 3D porous networks greatly prevent polycondensation of Ag3PO4 NPs because of the porous and interconnected microstructures, which enhanced the catalytic activity in the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) into a blue colored product (oxTMB) in the presence of H2O2. However, the addition of uric acid (UA) could lead to the reduction of oxTMB, resulting in fast fading of the blue color. Inspired by this finding, a simple and sensitive colorimetric assay for uric acid (UA) has been developed with a detection limit (LOD) of 0.94 μM. Furthermore, this strategy has been successfully applied to the detection of UA in practical samples.