【摘要】 以甲苯二异氰酸酯三聚体(TDI trimer)为耦合剂,将壳聚糖(CS)及聚乙二醇单甲醚(MeO-PEG)在5℃下,通过官能团耦合的方法合成了以TDI trimer为核,以单甲氧基聚乙二醇(MeO-PEG2000)和CS为臂的pH敏感性多核星型聚合物P(CS-TDI trimer-MeO-PEG)。用FTIR和1HNMR对产物的结构进行了表征,用凝胶渗透色谱(GPC)测定了多核星型聚合物的相对分子质量为2.42×106,其分布指数为1.64。用UV研究了其对辅酶A(CoA)的控制释放,结果发现,在24℃、w(多核星型聚合物)=0.001%-0.1%的pH=6.8水溶液中,随着w(多核星型聚合物)的增大对辅酶A吸附量增多;在w(多核星型聚合物)=0.01%、pH=3.7时,聚合物对辅酶A的吸附量最大;随着pH的增大,对辅酶A的吸附量减少,辅酶A从聚合物中释放出来。更多还原

【Abstract】 A novel kind of multiple cored star-shaped copolymers P(CS-TDI trimer-MeO-PEG)(Ⅰ) was synthesized by 2,4-tolylene diisocyanate(TDI) trimer,MeO-PEG,and chitosan(CS) at 5 ℃,with TDI trimer as core and MeO-PEG and CS as arm chains.The structure of the copolymer was characterized by FTIR and 1HNMR.The molecular weight and polydispersity determined by gel permeation chromatography(GPC) was 2.42×106 and 1.64 respectively.The results of UV analysis showed that at 24 ℃ and under w(Ⅰ) between 0.001% and 0.1%,the amount of absorbed coenzyme A increased with w(Ⅰ).At 24 ℃,w(Ⅰ)=0.01% and pH 3.7 of the solution,a large amount of coenzyme A was absorbed by the copolymer.The amount of absorbed coenzyme A decreased with increase of pH of the solution and coenzyme A was released from the copolymer.The results suggested that the copolymer could be used as drug delivery system.更多还原