A smart artificial glutathione peroxidase with temperature responsive activity constructed by host–guest interaction and self-assembly

Abstract

A smart supramolecular artificial glutathione peroxidase (GPx) with tunable catalytic activity was prepared based on host–guest interaction and a blending process. The functional guest molecules ADA-Te with catalytic center, ADA-Arg with binding site and the cyclodextrin-containing host polymers (CD-PNIPAMs) were first synthesized. The artificial glutathione peroxidase was constructed by host–guest interaction of ADA-Te and a series of CD-PNIPAMs with different molecular weights. Through altering the molar ratio of building blocks (CD-PNIPAM₇₃, ADA-Te, ADA-Arg), the optimum artificial GPx (SGPx_max) with vesicle structure was prepared via a blending process. Significantly, SGPx_max displayed a noticeable temperature responsive catalytic activity and exhibited typical saturation kinetics behavior of a real enzyme catalyst. It was proved that the change of the self-assembled structure of SGPx_max during the temperature responsive process played a significant role in altering the temperature responsive catalytic behavior. The construction of SGPx_max not only overcomes the insurmountable disadvantages existing in traditional supramolecular artificial GPxs but also bodes well for development of other biologically related functional supramolecular biomaterials.