Fabrication of Porous Proteinaceous Microspheres via One-Step Pickering Double Emulsions: Controllable Structure and Interfacial Cascade Biocatalysis

Methods based on double emulsions for producing porous microspheres have gained popularity as an effective and adaptable strategy. However, these microspheres are frequently composed of organic polymers that lack sufficient mechanical strength. Additionally, the conventional two-step process and the use of surfactants present notable challenges. A promising solution is to replace traditional surfactants with inorganic particles, utilizing a Pickering emulsion approach. Herein, we introduced a one-step approach for creating Pickering double emulsions, followed by a straightforward solvent evaporation process to produce porous proteinaceous microspheres. By harnessing the enhanced stability of Pickering emulsions, we can manipulate the morphology and pore structure of the microspheres by varying the oil-(ethanol/water) volume ratio, the size and type of emulsifier, ripening time, rotary evaporation temperature, and the addition of enzymes. Furthermore, we innovatively proposed the coencapsulation of glucose oxide (GOx) and horseradish peroxidase (HRP) for interfacial cascade catalysis, showing excellent catalytic activity, recovery, and reusability. This study presents a new, scalable approach for producing porous microspheres using a one-step Pickering double emulsion. It demonstrates significant potential for interfacial biocatalysis, and is expected to be applied in fields such as medicine, drug delivery, and biotechnology due to their suitability for encapsulating bioactive materials.