Preparation of 5-fluorouracil loaded chitosan/fibroin blend magnetic microspheres and its properties in vitro

OBJECTIVE To prepare 5-fluorouracil loaded magnetic microspheres with crosslinked chitosan and silk fibroin blend as the novel natural biodegradable wall materials and investigate their sustained release and magnetic responsive properties.METHODS The microspheres were prepared by emulsion cross-linking techniques.The release test of 5-Fu from magnetic CS/FB microspheres in vitro was carried out using constant temperature vibration dialysis assay.Magnetic responsive property was investigated using the apparatus of magnetic guidance experiment in vitro .RESULTS The sustained release and trapping efficiency of chitosan/ fibroin blend microspheres were better than those of chitosan microspheres.The release of 5-Fu from microspheres was decreased along with increased glutaraldehyde concentration.The drug release profile was described by Higuchi equation Q=2.744 8t 1/2 +35.261 3 (r=0.965 1),t _ 50 =28.83 h.Under the condition of magnetic restonsive intensity 0.4 T,medium flowing speed 1 cm·s -1 ,distance from the target site ≤3 cm,the accumulation percentage of microspheres containing 12% magnetite at the target site was above 75%.CONCLUSION Chitosan/fibroin blend magnetic microspheres may have potential application prospects in 5-Fu sustained release and targeted localization.