Study On Magnetic Nanomicells Applied In Drug Controlled Release System

A Series of magnetic nanomicelles was synthesized based on the SPIONs, the biocompatible polymer-Pluronic F127 or its copolymer with poly(DL-lactic acid) (F127-PLA) and folic acid via a facile chemical conjugation method. The magnetic nanomicelles were characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), vibrating sample magnetometer (VSM), dynamic light scattering measurements (DLS), transmission electron microscopy (TEM) and atomic force microscope (AFM).Firstly, SPIONs were prepared by modified chemical co-precipitation. Their superparamagnetic behaviors and high saturation magnetization values are able to broaden their biomedical applications.Secondly, SPIONs were chemically conjugated biocompatible Pluronic F127 and F127-PLA. The multifunctional magnetic nanoparticles formed into micelles in aqueous phase. Doxorubicin hydrochloride (DOX·HCl) was selected as a model anticancer drug to investigate the drug loading and release behaviors in the buffer solutions with different conditions. The Alamar blue assay was performed to evaluate the biocompatibility of the micelles and the antiproliferative effect of the drug-loaded micelles. The results displayed that the magnetic micelles were safe carriers and the DOX·HCl-loaded micelles suppressed the growth of the tumor cells.Finally, the magnetic nanomicelles conjugated with folic acid as a potential platform for dual targeted (folate-mediated and magnetic-guided) drug delivery were developed to enhance the efficiency and veracity of drug delivering to tumor site. DOX·HCl was selected to investigate the drug loading and release behaviors in different conditions. The Alamar blue assay was performed to evaluate the antiproliferative effect of the drug-loaded micelles. The results displayed that the treatment efficacy of the drug would be enhanced by application of permanent magnetic field and folic acid. Additionally, The primary in vivo tumor model study, which was carried out in VX2 tumor-bearing male New Zealand white rabbits, demonstrated that the nanomicelles could be guided into tumor site more efficiently by application of permanent magnetic field, and further represented significant therapeutic efficiency to solid tumor. Therefore, the magnetic micelles possess many great potential applications in nanomedicine fields.