PVP magnetic nanospheres: Biocompatibility, in vitro and in vivo bleomycin release

Purpose: To synthesize and characterize a magnetic micromolecular delivery system based on PVP hydrogel with polyvinyl alcohol (PVA) as the crosslinker. Methods: The microparticles were successfully prepared using 25 kGy Co-60 gamma-ray irradiation and characterized. Biocompatibility, in vitro and in vivo drug release tests were carried out. Results and discussion: Bleomycin was quantitatively released with in slightly over 8 h (hours) from the nanospheres containing 1 mg bleomycin while the time was longer for those containing 5 mg. On the other hand free bleomycin quantitatively passed through the dialysis baffle with in only 3.5 h. For both 5 and 1 mg of bound bleomycin, it took up to 2 h to reach peak concentration compared to 30 min for the free drug. Conclusion: The PVP hydrogel magnetic nanospheres exhibited passive drug release that could be exploited to enhance therapeutic efficacy. The present results indicate that PVP hydrogel based magnetic nanospheres have potential as drug carriers in magnetic guided chemotherapeutic drug delivery. (c) 2006 Elsevier B.V. All rights reserved.