Release Behavior and Cytotoxicity of Poly(vinyl alcohol)/Chitosan Blend Microspheres Containing 2,4-Dihydroxy-5-Fluoropyrimidine

Blend microspheres of poly(vinyl alcohol) (PVA) with chitosan (Cs) were prepared as candidates for oral delivery system. Cs/PVA microspheres containing 2,4-dihydroxy-5-fluoropyrimidine (5-FU) were obtained using glutaraldehyde (GA) as a cross-linking agent. The effects of cross-linker concentration and cross-linking time on the release of 5-FU were investigated, and the cytotoxicities of free 5-FU and the PVA/Cs microspheres loaded with 5-FU were also studied. It was observed that 5-FU release from the microspheres decreased with the increase of cross-linking concentration and cross-linking time. Cytotoxicity tests of free and entrapped 5-fluorouracil were carried out with MCF-7 breast cancer cell line. Free 5-FU produced an immediate effect, whereas entrapped 5-fluorouracil showed a prolonged cytotoxic effect.