Vitamin E dissolution in sulfobetaine zwitterionic surfactant solution andenhancement of dissolution by adding sodium chloride

Vitamin E is widely used in pharmaceutical, food and cosmetic preparations. This paper discusses methods of preparing vitamin E emulsions by using sul fobetaine (SB) zwitterionic surfactants which have high electrolyte toleran ce. The amount of vitamin E dissolved in water was analyzed by turbidity an d UV absorption measurements. The emulsion droplet size was determined by l aser light scattering. Microemulsions with small particle size and high res istance to oxidation in air can be obtained by solubilizing vitamin E in SE solutions at high concentrations (above 1%). The performance of a series o f SE surfactants is compared in 1.5% solutions. A SE surfactant with a 12 c arbon chain seems to be the most effective in dissolving vitamin E. The sat uration value of vitamin E is increased about one order of magnitude by add ing NaCl to the SE surfactant solutions. Emulsions formed in surfactant sol utions containing NaCl (0.4-0.6 M) are stable at low surfactant concentrati ons such as 0.2-0.4 %. The emulsion droplet sizes are below or around 200nm .