Yue Hu1,Benedetto Marelli1
MIT1
Yue Hu1,Benedetto Marelli1
MIT1
Pickering emulsion is a category of emulsion that is stabilized by solid particles. Compared to emulsions stabilized by molecular emulsifiers, Pickering emulsion has high stability, low cytotoxicity, and good biocompatibility. Solid particle emulsifiers could also be modified by functional groups or antibodies to achieve different demands. Thus Pickering emulsion is widely used in the food, pharmaceutical, and cosmetic industries. Silk-fibroin regenerated from silk cocoons is a natural protein. This fibrosis protein has been widely investigated and applied in the fields of biomedicine, cosmetics, and food coating. In our study, we developed biocompatible protein particles synthesized from silk fibroin to stabilize oleic acid oil-in-water Pickering emulsion. Those Pickering emulsions could be applied to agricultural and food industries.<br/><br/>Specifically, water-insoluble silk fibroin microparticles (SFMPs) with a diameter of approximately 2 µm were synthesized through the salting-out method. These microparticles can act as emulsifiers, stabilizing alkane-in-water Pickering emulsion. In addition, polar oil oleic acid with payloads possessing a p<i>K</i>a below 5 can be stabilized by SFMPs to generate a Pickering emulsion. The research also delves into the mechanism and ability of SFMPs to stabilize both nonpolar and polar oil-in-water Pickering emulsion, as evidenced by the measurement of three-phase contact angles. To functionalize Pickering emulsion, we synthesized antibody-labeled SFMPs, which can partially replace the emulsifier on the surface of Pickering emulsion droplets and improve the droplets' affinity to antibody binding sites. In this work, anti-pectic polysaccharide antibody-labeled Pickering emulsion loaded with plant hormone jasmonic acid exhibited strong binding to the waxy layer weaker part of the leaf even after the wash and effectively boosted the trichome number of <i>Arabidopsis</i> new leaf.