Magnetic drug targeting: Development of a novel drug delivery system for prostate cancer therapy.

摘要

Magnetic nanoparticles (MNPs) have been attracting a great amount of attention because of their numerous applications including contrast agents in magnetic resonance imaging (MRI), magnetic targeted drug carriers, and hyperthermia treatments for cancer. However, complications, including aggregation of MNPs, have limited their use in drug delivery applications. To overcome these limitations, several methods have been developed to coat magnetic particles. One method includes coating them with polymers to produce polymer/MNPs for increasing the MNP dispersion and stability. This method also increases the efficiency of loading and releasing drugs to specific locations for the treatment of various diseases including prostate cancer.;The major objective of this research project was to develop polymer magnetic nanoparticles (PMNPs) using a silane coupling agent and a novel thermo-sensitive polymer, N-isopropylacrylamide-acrylamide-allylamine (NIPA-AAm-AH). The temperature-sensitive polymers were chosen as a shell for the purpose of creating a controlled drug delivery system. In this system, the temperature induced by the magnetic core would be used to release therapeutic agents from the polymer shell at a specific location. The chemical and physical properties of these PMNPs were determined using Fourier transformed infrared spectroscopy, nuclear magnetic resonance, x-ray photoelectron spectroscopy, and a superconducting quantum interference device. Transmission electron microscopy indicated the size of our PMNPs were about 100 nm. These nanoparticles had a better biocompatibility in comparison to the original MNPs using cytotoxicity assays (e.g. MTS assays). Moreover, bovine serum albumin (BSA) and doxorubicin release profiles from the nanoparticles indicated that our PMNPs released drugs in response to changes in temperature. Finally, results from iron assays and parallel flow chamber systems, with external magnets used to assess the cellular uptake and in vitro localization of the synthesized nanoparticles, indicated that these nanoparticles would provide a means for magnet targeting capabilities.