Preparation of chitosan/chondroitin sulfate complex microcapsules and application in controlled release of 5-fluorouracil

Chitosan/chondroitin sulfate complex microcapsules were prepared to encapsulate the anti-cancer drug 5-fluorouracil (5-Fu) by emulsion-chemical crosslinking method. The microcapsules were characterized by Fourier transform infrared spectroscopy (IR), scanning electron microscopy (SEM) in conjunction with energy dispersive X-ray spectrometry (EDS), and laser diffraction particle size analysis. The in vitro drug release behavior of 5-Fu from the microcapsules was studied by UV–visible spectrophotometry. Results showed that the microcapsules were in spherical form with diameter mostly in the range of 20–60 μm. Result of EDS showed that 5-Fu was in the internal core of the microcapsules. The IR spectrum indicated that electrostatic interactions exit between chitosan and chondroitin sulfate, with the sulfate group and free carboxyl group reacted with the amino groups of chitosan. The release kinetic experiments showed that the release performance of the microcapsules was influenced by the amount of crosslinking reagent, drug loading and the pH of the release medium.