Ferritin as a bionano-particulate emulsifier.

Stable 'Pickering-type' emulsions were prepared using ferritin, a spherical protein, as a bionano-particulate emulsifier and n-dodecane, toluene, castor oil, olive oil or vegetable oil as an oil phase, in the absence of any surfactant molecules. All the emulsions prepared were of the oil-in-water type and an increase of ferritin concentration decreased the volume average droplet diameters. Transmission electron microscopy studies of the ferritin residues remaining after evaporation of oil and water from the emulsion revealed a broken capsule morphology, which is strong evidence for the attachment of ferritin at the oil-water interface thereby stabilizing the emulsion. The emulsion droplets could be elongated and made to pass through a glass capillary.