| abstract |
A method of entrapping a water-soluble substance in vesicles formed from a surface active siloxane is carried out by dissolving the substance to be entrapped in water, adding the surface active siloxane, mildly agitating the mixture, and removing excess water and substance. Water-insoluble substances are entrapped in the vesicles by dissolving the substance to be entrapped in the surface active siloxane, and mildly agitating the substance and the siloxane. The surface active siloxanes consist essentially of tetravalent SiO2 units, and monovalent R3SiO+E,fra 1/2+EE and R'R2SiO+E,fra 1/2+EE units. The ratio of monovalent units to tetravalent units is from 0.4/1 to 2/1, and from 40 to 90% of all monovalent units are R'R2SiO+E,fra 1/2+EE units. R is a monovalent hydrocarbon group with up to eight carbon atoms, and R' is a polyoxyalkylene group. |