Although Camptothecin (CPT) has significant antitumor activity to lung, ovarian, breast, pancreas, and stomach cancers; lactone
ring opening causes a reduction in cytotoxic activity and severe side effects in physiological conditions (pH: 7.4, 37°C) due to decreased
cell membrane binding, membrane diffusibility, and intrinsic potency against the topoisomerase target. Taken into consideration
the targeted delivery advantage of biocompatible magnetic particles, in order to contribute to the removal of the handicap (lactone ring
opening), the current study investigated stability, release, and in vitro bioactivity of CPT in oleic acid (OA)-pluronic F127 (PL) coated
iron oxide micro and nanoparticles. CPT encapsulated magnetite micro (~10 μm) and nano (~30 nm) formulations were synthesized
without changing their magnetic properties. Analysis of encapsulated CPT illustrated that over 99% of the lactone form was protected in
the magnetic particle formulations and release of CPT from the magnetic micro and nanoparticles lasted for 9 and 4 days respectively. In
addition, in a representative in vitro cytotoxicity study, CPT encapsulated OA-PL stabilized magnetite microparticles were approximately
65% more effective than free CPT to inhibit 100% cell growth on three different human liver carcinoma cell lines. Therefore, the OA-PL
stabilized iron oxide formulation is ideal for achieving targeted and sustained CPT delivery in bioactive lactone form to overcome its
handicaps in clinical conditions.
Keywords: Cancer chemotherapy, cell culture, targeted drug delivery, microparticles, nanoparticles, camptothecin, iron oxide.
Rights & PermissionsPrintExport