Preparation Of The Multi-responsive Polymer Microspheres And Application In Controlled Drug Release

In recent years, composite microspheres by encapsulation organic or inorganic microspheres with different polyelectrolytes have been extremely wide attention. In this work, different responsive microspheres were prepared by the LbL self-assembly technique for the drug controlled release. It mainly included several sections as follows.1. In order to avoid the aggregation of the noncovalent-assembled polyelectrolyte microspheres in media with high ionic strength, the aldhyde-terminated polyethylene glycol (APEG) was grafted on the surface of the polyelectrolyte microspheres via the nucleophilic addition between the amino group of CS and aldehyde groups of APEG. It was found that the surface APEG grafting on the hollow microspheres could prevent aggregation in the media with high salt concentration.2. The hybrid microspheres have been accomplished via the layer-by-layer (LBL) self-assembly alter adsorption CS-g-PEG and Fe3O4-CA on the sulfonated polystyrene template, etched the templates. The in vitro biocompatibility and the magnetic tests of the hollow microspheres indicated that the hollow microspheres showed good biocompatibility and magnetic response. The saturation magnetization of the hollow microspheres was37.23emu/g.3. The high magnetic hybrid shell was fabricated by the electrostatic interaction between the CS-g-PEG, Fe3O4-LYs and the hybrid anion of FesO-CA onto the polystyrene sulfonate microspheres, and then etched the PSS. The saturation magnetization of magnetic polyelectrolyte hybrid hollow microspheres was45.69emu/g. Fe3O4-CA and Fe3O4-LYs account for69.36%of the hollow microspheres.4. We prepared the polymethacrylate microspheres with different crosslinker by the distillation precipitation polymerization and adsorbed the different layers of chitosan and alginate on polymethacrylate microspheres. Investigated the drug loading and controlled release of the different microspheres.