Preparation of 5-Flurouracil Loaded Microspheres

Polylactide (PLA) is a kind of biodegradable and biocompatible material. In recent years, polylactide (PLA) and its copolymers have received significant attention from researchers. 5-Fluorouracil (5-Fu) is an antimetabolite of the pyrimidine analog type and is widely used for cancer treatment. As many other kinds of hydrophilic medicines, 5-Fu is difficult to be encapsulated by a water-in-oil-in-water emulsion solvent evaporation technique and the drug content is affected by the volume of the internal phase the increase in which resultes in a decrease in the yield of microspheres. In this study, 5-Fu loaded PLA microspheres which has quite high yield were prepared by a particular oil-in-water evaporation method. During the process of microspheres preparation, nano-silica was used in order to achieve high drug content. The size and morphology of the microspheres were observed by the scanning electron microscope (SEM). According to the results, these microspheres have smooth, spherical surface structure, with no apparent evidence of collapsing which can ensure the even release of the drug. Their size depends on the concentration of dispersed phase and gelatin and the size of nano-silica particles. The nano-silica content was determined by thermogravimetry analyzer (TGA) and by a spectrophotometer, the 5-Fu content in the microspheres could be calculated. It was shown that the PLA microspheres containing lower amount of nano-silica have higher ability to incorporate 5-Fu.