Lyophilized paclitaxel magnetoliposomes as a potential drug delivery system for breast carcinoma via parenteral administration:: In vitro and in vivo studies

Purpose. The study reports in vitro and biological evaluation of lyophilized negatively charged paclitaxel magnetic liposomes as a potential carrier for breast carcinoma via parenteral administration. Methods. Paclitaxel in magnetoliposomes were extracted by centrifugation and quantified by high-performance liquid chromatography ( HPLC). Biological properties were studied using pharmacokinetics, in vivo distribution and cytotoxicity assays, as well as a mouse model of EMT-6 breast cancer. Results. Pharmacokinetic studies showed that encapsulation of paclitaxel in magnetoliposomes produced marked difference over the drug in Cremophor EL/ethanol pharmacokinetics, with an increased t(1/2 beta) 19.37 h against 4.11 h. For in vivo distribution, paclitaxel concentration of lyophilized magnetoliposomes in the tumor was much higher than that of lyophilized conventional liposomes or Cremophor EL/ethanol, whereas in heart it was much lower than the latter two formulations via s.c. and i.v. administration. Lyophilized paclitaxel magnetic liposomes showed more potency on the therapy of breast cancer than other formulations via s.c. and i.p. administration. Conclusions. The current study demonstrates that paclitaxel magnetoliposomes can effectively be delivered to tumor and exert a significant anticancer activity with fewer side effects in the xenograft model.