Preparation of Superparamagnetic Iron Oxide Nanoparticles Stabilized by Water- Soluble Chitosan -g- poly(ethylene oxide)

摘要

Chitosan, one of basic polysaccharides, as a N-deacetylated product of chitin which is the second large amount of natural polymer, has received a great attention in the biomedical field because it exhibits many unique biological properties such as antibacterial, biocompatibility, degradability, non-toxicity. Specifically, chitosan has been used in wound dressing, wound healing, drug delivery systems, functional foods, and various tissue engineering applications. However, the quite low solubility for neutral water, i.e., the main problem, should be solved to overcome its limited application field although it is soluble in dilute aqueous acid (pH <6.5). With this regard, the development of its chemical modifications become a major research field. There are many water-soluble chitosan derivatives via modifications involving the amine group (NH2) at the C-2 position or the hydroxyl groups at the C-3 and C-6 positions such as N- carboxymethylation, sulfonation, quaternization, and N- and O- hydroxylation. To obtain a good solubility in water, most glucosamine units of the chitosan chain should be modified.