Enzyme–Polymer Conjugates as Robust Pickering Interfacial Biocatalysts for Efficient Biotransformations and One‐Pot Cascade Reactions

Abstract

Despite the rapid development of Pickering interfacial catalysis (PIC) at liquid-liquid interfaces with chemocatalysts, the use of unstable biocatalysts at emulsion interfaces remains a technical challenge. Herein, we present a Pickering interfacial biocatalysis (PIB) platform based on robust and recyclable enzyme-polymer conjugates that act as both catalytic sites and stabilizers at the interface of Pickering emulsions. The conjugates were prepared by growing poly(N-isopropylacrylamide) on a fragile enzyme, benzaldehyde lyase, under physiological conditions. The mild in situ conjugation process preserved the enzyme structure, and the conjugates were used to emulsify a water-organic two-phase system into a stable Pickering emulsion, leading to a significantly larger interfacial area and a 270-fold improvement in catalytic performance as compared to the unemulsified two-phase system. The PIB system could be reused multiple times. Conjugates of other enzymes were also fabricated and applied for cascade reactions.

Enzyme-Loaded Mesoporous Silica Particles with Tuning Wettability as a Pickering Catalyst for Enhancing Biocatalysis

“…One includes free enzymes located in the inner aqueous phase [12][13][14][15][16][17]. The other includes enzyme-immobilized particles anchored around droplet interfaces [18][19][20][21][22][23][24][25][26], by contrast, it enables enzymes to be recycled, maximizes the contact area between enzymes and substrates, reduces diffusion distance of substrate molecules and improves the stability of enzymes. In the above two kinds of Pickering catalysis system, the changing of the organic-aqueous phases ratio or increasing particulate emulsifiers concentration is applied to improve interfacial area to enhance the enzymatic reaction.…”

Two‐Dimensional Mesoporous Carbon Materials Derived from Fullerene Microsheets for Energy Applications

“…Note that all the carbonized samples imply an amorphous state and a defective structure. Therefore, excellent ORR electrocatalytic activities are expected for the as‐obtained defect‐rich FMS1000 …”

Sodium caseinate as a particulate emulsifier for making indefinitely recycled pH-responsive emulsions

“…10,11 For emulsion interface catalysis (EIC), the efficient separation and recycling of catalysts are one of the major objectives of sustainable and green chemistry. 12,13 However, the catalysts in EIC have traditionally been separated and recycled via centrifugation and ltration, which are timeand energy-consuming. To address this issue, engineered "smart" emulsiers, in particular inorganic or polymeric particles, have been developed recently to produce emulsions that are responsive to external stimuli such as pH, 12 temperature, 14 light, 15 and chemical agents.…”