Self-assembled Cr2O3@nanogel/Au nanozymes to simulate peroxidase activity as a H2O2 sensor

The low temperature solvothermal method synthesized Cr 2 O 3 NPs has not only peroxidase activity, but also oxidase activity. Then, the oxidase activity of Cr 2 O 3 NPs is effectively shielded by nanogel immobilization using three monomers acrylamide, NIPAAM (N-isopropylacrylamide) and MBA (N,N′-methylene bisacrylamide) in HEPES (4-(2-hydroxyerhyl)piperazine-1-erhanesulfonic acid) buffer. Ultimately, the enzymatic activity of Cr 2 O 3 @nanogel/Au is significantly enhanced after doping Au NPs by SERS (Surface Enhanced Raman Spectroscopy) evaluation. A SERS strategy was proposed for the detection of H 2 O 2 by Cr 2 O 3 @nanogel/Au. The linear range was 10 −8  mol·L −1 -10 −1  mol·L −1 .