title: Hydrophobin coated boehmite nanoparticles stabilizing oil in water emulsions.
abstract: Hydrophobin coated boehmite nanoparticles have been used to establish tooth-paste like, homogenous emulsions. The surface-modified nanoparticles were simply obtained by mixing aqueous solutions of cationic boehmite particles with the anionic hydrophobin H Star Protein B® (HPB). Surface tension measurements clearly show that 1 wt.% boehmite binds up to 1 wt.% HPB. The strong interaction and aggregation of hydrophobin coated boehmite nanoparticles was proven by Cryo-TEM measurements, too. Interestingly, the combined use of 0.5 wt.% HPB and 0.5 wt.% boehmite as emulsifying agents resulted in very stable, homogenous, high internal phase emulsions (65 wt.% oil) that are stable over months. The established emulsions have also been characterized by rheological measurements. Storage moduli of more than 1000 Pa are characteristic for their high gel-like properties. Furthermore, light microscopy showed an average droplet size close to 1 μm with low polydispersity. Cryo-SEM confirmed that the hydrophobin coated nanoparticles are located at the interface of the oil droplets and therefore stabilize the emulsion systems.
authors: University of Bayreuth, BZKG/BayColl, Gottlieb-Keim-Strasse 60, 95448 Bayreuth, Germany. Martin.Reger@uni-bayreuth.de
authors: Martin
authors: M
authors: Reger
authors: Heinz
authors: H
authors: Hoffmann
mesh_terms: D000536:Aluminum Hydroxide / Q000737:chemistry*; D000537:Aluminum Oxide / Q000737:chemistry*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D004655:Emulsions / Q000737:chemistry*; D053758:Nanoparticles; D009821:Oils; D013499:Surface Properties; D013501:Surface-Active Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry*
chemical_list: D020099:Coated Materials, Biocompatible; D004655:Emulsions; D009821:Oils; D013501:Surface-Active Agents; D014867:Water; D000536:Aluminum Hydroxide; C069471:aluminum oxide hydroxide; D000537:Aluminum Oxide