Fabrication of Dual-Stimuli-Responsive Polymer Vesicles for Regulation of Enzymolysis Efficiency in A Cascade Reaction.

Abstract

Enzymatic cascade reactions in confined microenvironments play important roles in cellular chemical transformation. Controlling enzymatic efficiency and eliminating substrate interference in cascade reactions is of great significance. To this end, a vesicle composed of poly(styrene-maleic anhydride-N-isopropylacrylamide)(P(S-M-NIP)) and functionalized with 1,2-bis(10,12- tricosadiynoyl)-sn-glycero-3-phosphocholine (DC89 PC) was designed herein. Based on the thermo-sensitive property of P(S-M-NIP) and the photo-responsive property of DC89 PC, a serial of dual-stimuli-responsive nanoreactors was constructed via enzymes encapsulation to tune their enzymolysis efficiencies. A kinetics study of the glucose oxidase-encapsulated nanoreactor indicated that its enzymolysis velocity increased 2.1- and 1.6-fold under heating and the ultraviolet (UV)-light irradiation, respectively. Consequently, an enzymatic cascade reaction in the proposed enzyme reactor encapsulated with β-galactosidase and glucose oxidase was investigated. The results revealed a 2.9-fold enhancement in enzymolysis efficiency by changing the ambient temperature under UV irradiation. The dual-stimuli-responsive polymer vesicles could also eliminate H2 O2 interference during the enzymatic cascade reaction. The vesicles demonstrated potential for switch-membrane-permeability, while, the confined microenvironment played a key role in regulating the reactions upon the temperature change and the presence of UV light. Our synthetic multi-organelle-like system provides a new way to mimic the control of cascade reaction catalytic processes by programming the "open/close" sates of the nanocapsules.