Electrochemical Stimulated Pickering Emulsion for Recycling of Enzyme in Biocatalysis.

Potential-stimulated Pickering emulsions, using electrochemical responsive microgels as particle stabilizers, are prepared and used for biocatalysis. The microgels are constructed from cyclodextrin functionalized 8-arm poly(ethylene glycol) (8A PEG-CD) and ferrocene modified counterparts (8A PEG-Fc) via CD/Fc host-guest chemistry. Taking advantage of the redox reaction of Fc, the formation and deformation of the microgels and corresponding Pickering emulsions can be reversibly stimulated by external potential, and have been used for the hydrolysis of triacetin and kinetic resolution reaction of (R,S)-1-phenylethanol catalyzed by lipases. Potential stimulated destabilization of the emulsion realizes an effective separation of the products and enzyme recycling.