A facile one-pot method to prepare peroxidase-like nanogel artificial enzymes for highly efficient and controllable catalysis.

Graphical abstract Highlights • One-pot polymerization to prepare nanogel-based artificial enzymes, which is facile and scalable. • NAEs are much more stable than the natural HRP in a broad range of temperature and pH. • NAEs have a good enzymatic activity on several azo compounds. • NAEs are temperature-switchable, and have a great potential in controllable catalysis. Abstract Novel artificial enzymes are highly desired to overcome the shortcomings of natural enzymes during industrial or biological applications. Here we designed and prepared nanogel-based artificial enzymes (NAEs) to mimic natural horseradish peroxidase (HRP) using a facile one-pot, scalable method. The poly(N-isopropylacrylamide) (PNIPAM) matrix provided a temperature-responsive and size-controllable scaffold for the NAEs, and 1-vinylimidazole (Vim) moieties stabilized the enzymatic centers (Hemin) through coordination interaction. The feeding ratios of the components to prepare NAEs were subsequently studied and optimized to ensure the NAEs possess the highest catalytic activity and stability. The optimized NAEs were quite stable and can maintain their catalytic activities over a broad range of heat or pH treatments, and a long storage period as well. The NAEs are active to catalytic oxidation of several azo compounds and their activities can easily be switched on/off by changing the surrounding temperature. Taken together, these easily made, highly stable, efficient and activity-switchable NAEs could mimic natural HRP while overcoming their shortcomings and have a potential in wastewater treatment and controllable catalysis. [ABSTRACT FROM AUTHOR]