Preparation and characterization of Mitomycin-C loaded chitosan-coated alginate microspheres for chemoembolization

Mitomycin-C loaded and chitosan-coated alginate microspheres were prepared for use in chemoembolization studies. In this respect, first alginate microspheres were prepared by using a spraying method using an extrusion device with a small orifice and following suspension cross-linking in an oil phase. Chitosan-coating onto the alginate microspheres was achieved by polyionic complex formation between alginate and chitosan. CaCl(2) was used as a cross-linker for alginate microspheres. The obtained chitosan-coated alginate microspheres were spherical shaped and approximately 100-400 microm average size. The microspheres were evaluated based on their swellability and the swelling ratio was changed between 50-280%. CaCl(2) concentration, stirring rate, chitosan molecular weight, chitosan concentration and time for coating with chitosan were selected as the effective parameters on microsphere size and swelling ratio. Equilibrium swellings were achieved in approximately 30 min. On the other hand, chitosan molecular weight, chitosan concentration and time for coating with chitosan were found as the most effective parameters on both drug loading ratio and release studies. Maximum drug loading ratio of 65% was achieved with high molecular weight (HMW) chitosan, highest chitosan concentration (i.e. 1.0% v/v) and shortest time for coating with chitosan (i.e. 1 h) values.