The Application of Thermosensitive Magnetic Nanoparticles in Drug Delivery

Abstract

In this study, thermosensitive and magnetic nanoparticles were synthesized by reverse microemulsion and radical polymerization. Thermo-sensitive and magnetic nanoparticles consist of 6nm magnetite core (Fe3O4) and silica shell which then grafted by poly (N-isopropylacrylamide) (PNIPAM). The morphologies of these fabricated nanoparticles were observed by SEM and TEM, which is confirmed to be the core-shell structure. The property of PNIPAM could change from hydrophilic to hydrophobic from low temperature to high temperature. The lower critical solution temperature measured by DSC and DLS is at ~35°C. The magnetic characteristic of these nanoparticles is analyzed by SQUID. The result is illustrated as superparamagnetic behavior for the nanoparticles. Therefore, the nanoparticles could be introduced to the desired location by external magnetic field due to magnetite core. The absorption and desorption of Bovine serum albumin (BSA) were also discussed. At 50°C, the BSA can be absorbed by the polymeric shell presented as hydrophobic chains and be desorbed ~70% at room temperature. Combined thermosensitive and magnetic properties, nanoparticles could be utilized in controlled drug –targeting delivery.