Abstract
Two types of oil-in-water emulsions consisting of oleic acid-or ethyl oleate-based magnetic fluid as the dispersed phase in water were prepared with casein as the emulsifier, and their characteristics relating to the emulsion stability were investigated. The mean droplet diameter of ethyl oleate- or oleic acid-based magnetic emulsion was 5.0 or 6.4 μm, respectively. Visual observation of sedimentation volume revealed that ethyl oleate-based emulsion was more stable than oleic acid-based emulsion, and this observation was in accord with the experimental results of droplet number of each emulsion. Concerning the rheological properties, oleic acid- or ethyl oleate-based magnetic fluids showed non-Newtonian flow, but the emulsions prepared from both fluids showed Newtonian flow. These results indicate that ethyl oleate-based magnetic emulsion may be superior to oleic acid-based magnetic emulsion as a magnetic drug-carrying material.
