Iron oxide/PLGA nanoparticles for magnetically controlled drug release

Abstract

Recently, nanoscale stimuli-responsive devices have received much attention thanks to their potential to limit the cytotoxic effect of the therapeutic treatment at the diseased tissue. Among different physical triggers, large alternating magnetic fields enable the conversion of magnetic energy into heat by using magnetic nanoparticles that generate localized hyperthermia, named Magneto Fluid Hyperthermia (MFH). This methodology can be exploited for cancer therapy or/and thermally activated drug release. The small size iron oxide nanoparticles (Fe-NPs), such as SPIO (small iron oxide particles) and USPIO (ultra-small iron oxide particles), currently used for this application have many limitations due to their 1) high intratumor concentration needed due to the low heating power 2) short particle blood-half-life, 3) non-specific distribution, 4) low internalization efficiency. For these reasons many efforts are necessary to make magneto fluid particle hyperthermia (MFH) a competitive tumor therapy for clinical applications. New iron oxide nanoparticles, coated with oleate, with a diameter of 5-18 nm, have been prepared by co-precipitation and incorporated into PLGA-NPs (PLGA=Poly(lactic-co-glycolic acid) in order to improve their biocompatibility and ``in vivo'' stability. Moreover, PLGA-NPs have been loaded with both NPs-Fe and antitumor drugs (Paclitaxel, PTX), an anticancer hydrophobic drug used in the treatment of ovarian and breast cancer, to perform MFH triggered drug release. The PTX and Fe-NPs loaded nanoparticles may be considered as an effective anticancer drug delivery system for Imaging-guided hyperthermic treatment of tumors.