摘要
目的:合成满足植入给药载体要求的温度敏感型PLGA-PEG-PLGA嵌段共聚物,并对其结构和性质进行研究。方法:采用开环聚合法,以不同比例的丙交酯、乙交酯和PEG为原料,异辛酸亚锡为催化剂,合成PLGA-PEG-PLGA嵌段共聚物。通过考察不同嵌段共聚物的相变温度和黏度,筛选确定符合植入给药载体要求的合成条件和投料比例。结果:合成的凝胶材料,经FTIR和1H-NMR检测,材料符合PLGA-PEG-PLGA嵌段共聚物特征。经筛选,按丙交酯-乙交酯-PEG1500(6∶1∶3)的质量比投料,0.1%(W/W)催化剂用量,在真空条件下140℃反应12h,可以得到满足植入给药要求的载体材料。结论:采用开环聚合法,可以合成温敏型PLGA-PEG-PLGA嵌段共聚物,其相变温度可通过改变丙交酯、乙交酯投料比例和PEG的相对分子质量在一定范围内调节。实验合成的共聚物在质量分数为20%时,相变温度35℃,黏度与55%甘油水溶液相当,形成的凝胶具备一定的刚性,材料无有机溶剂残留,符合植入给药载体的要求。
OBJECTIVE To synthesize the thermosensitive PLGA-PEG-PLGA copolymer suited for the implantable drug delivery system and to study on the structure and basic properties of the copolymer. METHODS The PLGA-PEG-PLGA triblock copolymer was synthesized via typical ring-opening polymerization method of different ratios of DL-lactide. glycolide and poly-ethylene glycol（PEG） using Tin（Ⅱ）-2-ethylhexanoate as the catalyst. The ideal material was screened and determined by investigating the phase transition tempretures and viscosities of different copolymers. RESULTS The synthetic product exhibited reversible thermosensitive sol-gel transition behavior, Its structure was identified by FTIR, ^1H-NMR it could fit the characteristic of the PLGA-PEG-PLGA copolymer. The copolymer could be prepared at 140℃ for 12 hours under vacuum with the prescribed weight ratio of LA-GA-PEG1500（6：1 ： 3） and the catalyst （0. 1%, W/W）. CONCLUSION The thermosensitive PLGA-PEG- PLGA copolymer can be synthesized via typical ring-opening polymerization method. To a certain extent, the gelation tempreture can be adjusted by changing various parameters such as LA/GA ratio, PEG molecular weight. The 20%（W/W） gel solution possesses suitable gelation tempreture（35℃） and viscosity（similar to 55 % glycol solution） could form into gel of gentle hard and be free of organic solvents, which can meet the needs of carriers for implantable drug delivery system.
出处
《中国医院药学杂志》
CAS
CSCD
北大核心
2008年第21期1845-1848,共4页
Chinese Journal of Hospital Pharmacy
