Self assembled magnetic PVP/PVA hydrogel microspheres; magnetic drug targeting of VX2 auricular tumours using pingyangmycin

Chemotherapy in cancer treatment is associated with serious side effects and as a result there is great interest in research aimed at bringing down the level of systemic cytotoxicity. With advances in material science, magnetic drug targeting has emerged as one of the viable ways of attaining this. In this study, we used self assembled PVP/PVA magnetic hydrogel microspheres to deliver pingyangmycin (Bleomycin A5) to rabbit auricular VX2 tumours in the presence of a 0.5 T permanent magnet both during and 24 h after perfusion. A total of 22 New Zealand white rabbits ranging from 13 to 16 weeks and weighing 2.5-3.0 kg (2.46 +/- 0.2) successfully implanted with tumours 200-300 mm 2 in size were used. In group D (1 mg pingyangmycin in 50 mg ferrofluid without a magnet) 2 weeks post treatment, there was statistically significant difference compared to the control (p = 0.05) in favor of group D. However, when compared to the group with 1 mg pingyangmycin(BLM) in 50 mg of ferrofluid and 0.5 mg (BLM) in 50 mg ferrofluid both with a permanent magnet in place for 24 h, the statistically significant difference was in favor of combined treatment, i.e. ferrofluid carrying drug in presence of a permanent magnet (p = 0.01). The microspheres in conjunction with the magnet did deliver pinyangmycin to the tumour and hence may be of use in future as far as magnetic drug targeting is concerned. However, more studies are still required to establish biodistribution and biostability not to forget drug release of ferrofluid of different chemotherapeutic agents available.