Construction of smart glutathione peroxidase mimic based on hydrophilic block copolymer with temperature responsive activity.

A temperature-sensitive block copolymer (PAAm-b-PNIPAAm-Te) with a glutathione peroxidase-like active site was synthesized via ATRP. As a new glutathione peroxidase (GPx) mimic, it displays typical saturation kinetic behaviors and high catalytic activity. More importantly, the catalytic activity of the polymer can be well modulated by changing the temperature. The experiments proved that a change in the self-assembly structure of the polymer plays a key role for the modulation of catalytic activity. As a contrast, another block copolymer, PAAm-Te-b-PNIPAAm, was synthesized. In comparison with PAAm-b-PNIPAAm-Te, the different temperature dependent catalytic behavior seen further indicates that the micellar structure plays an important role in modulating the catalytic activity of the smart enzyme model.