Synthesis and Characterization Micelles that Contain Free Amine Groups — Amphiphilic Poly (ε-caprolactone) – Chitooligosaccharide – Poly (ethylene glycol) copolymer and its applications in Drug Delivery

• Main Authors: Jean-Dean Yang, 楊政典
• Other Authors: Tze-Wen Chung
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/4vw7b6

碩士 === 中原大學 === 醫學工程研究所 === 92 === A new biodegradable amphiphilic copolymers, Poly (��-caprolactone) – chitooligosaccharide – poly (ethylene glycol) (PCL-g-COS-g-PEG, PCP) which contains free amine groups of COS, were synthesized and characterized. The characteristics of the PCP copolymers were examined by 1H Nuclear magnetic resonance (1H NMR), Fourier-transform infrared spectrometry (FT-IR) for function group analysis and Gel permeation chromatography (GPC) for determining molecular weight. The PCP copolymers can self-assembly to form micelles at the critical micelle concentration (CMC) about 8×10-3–1.6×10-2 wt.% (80 ~ 160 mg/L), determined by measuring UV-VIS absorption spectra of DPH loaded PCP micelles. Moreover, the average diameter of PCP micelles were 68.5 nm measured by a dynamic light-scattering (DLS) analyzer. The morphology of micelles was observed by Transmission Electron Microscopy (TEM) with sizes ranged from 20 to 120 nm. After the PCP copolymer was grafted with RGD by photochemical technique based on phenyl azido chemistry. For comparing the targeting capability of micelles, the RGD grafted PCP micelles (RGD-PCP) and PCP micelles was used to target PC-12 cell in vitro study. The results showed that RGD-PCP micelles were faster targeting capability than PCP micelles, and the free amine group of PCP micelles could be further crosslinked using a natural crosslinker, such as genipin, to improve the stability of the micelles. The new synthesized PCP copolymers and micelles containing amine groups can be further applied by chemical modification for drug delivery.