Preparation of controlled release anticancer agents. I: 5-Fluorouracil-ethyl cellulose microspheres.

Microspheres of 5-fluorouracil have been prepared, using three grades of ethyl cellulose as wall forming materials, and utilizing a solvent evaporation technique under ambient conditions. An alcoholic solution of 5-fluorouracil and polymer was dispersed in liquid paraffin containing 33.3 per cent n-heptane. The effect of stirring rate, time of stirring, drug loading, and polymer grade on drug release in two different media were evaluated. The drug loaded particles were spherical in shape and had a diameter range of 25-200 mm and were suitable for incorporating into a gel base. Drug release studies in aqueous media, showed that acidic media provide a faster release rate than neutral media. The drug release study from an aqueous gel base preparation at pH 7.0 through a synthetic membrane was found to be promising for formulation of a gel-microsphere product for the treatment of skin lesions.