Fabrication Of Multifunctional Magnetic Chitosan Microcapsule Via Sonochemical Method And The Study On Their Performances

Chitosan is a kind of natural polymer materials, and widely exists in nature. Among the commonly-used biomaterials, chitosan is seen as one of the most promising materials for pharmaceutical applications, ascribing to its advantages of superior biocompatibility, high charge density and non-toxicity. It has been widely used as materials of drug carriers in drug delivery systems.This thesis mainly introduces fabrication of multifunctional magnetic chitosan microcapsule via sonochemical method and studies on their performances. Here, we demonstrate the possibility to build a multifunctional drug delivery system based on magnetic Fe3O4 NPs, chitosan and folate molecular and so on.The second chapter of this thesis mainly introduces that magnetic and pH-responsive chitosan microcapsules(MPRCMCs) were prepared by a simple sonochemical method. Superparamagnetic oleic acid modified Fe3O4 nanoparticles(OA-Fe3O4 NPs) and hydrophobic drugs could be directly loaded into MPRCMCs during sonication. The microcapsules showed an excellent magnetic property. In addition, the pH-responsive controlled release of coumarin 6(C6) from MPRCMCs indicated that the developed microcapsules could be a promising candidate for drugs carriers. In addition, the influences of ultrasonic intensity, concentration of chitosan solution on the morphology and size of MPRCMCs were investigated in detail.The third chapter of this thesis mainly introduces folic acid(FA) functionalized magnetic chitosan(CS) microcapsules(FA-MCMCs) were fabricated by a simple sonochemical method. FA molecules were coupled onto the outer walls of microcapsules as targeting ligands. Oleic acid(OA) modified Fe3O4 nanoparticles(OA-Fe3O4 NPs) and hydrophobic drugs were encapsulated into microcapsules. FA-MCMCs showed an excellent supermagnetic and molecular targeted property. Cellular uptake of C6-loaded FA-MCMCs proved that FA-MCMCs could be endocytosed into the cells with the folate receptors selectively. Besides, FA-MCMCs showed a good pH-responsive and thermosensitive property. The developed FA-MCMCs could be a promising candidate for anti-cancer drugs carriers.