How controlled and versatile is N-carboxy anhydride (NCA) polymerization at 0 °C? Effect of temperature on homo-, block- and graft (co)polymerization
How controlled and versatile is N-carboxy anhydride (NCA) polymerization at 0 °C? Effect of temperature on homo-, block- and graft (co)polymerization
复制标题
DOI：
10.1039/b9py00337a
复制
发表时间：
2010-06-01
影响因子：
4.6
通讯作者：
Heise, Andreas
中科院分区：
文献类型：
--
作者：
Habraken, Gijs J. M.;Peeters, Maloes;Heise, Andreas
我们研究了各种氨基酸 N-羧酸酐 (NCA) 在 0 摄氏度下的聚合。对三种氨基酸 NCA 均聚的详细 MALDI-ToF 分析清楚地证实，在 0 摄氏度下不存在经常发生的端基终止和其他副反应。聚合因此受到控制，并获得了可溶性多肽的多分散性较低的同聚和共聚肽，约为 1.1。 MALDI-ToF 等高线图分析证实了共聚物的随机性。由多肽大分子引发剂成功合成嵌段共聚物进一步验证了低温NCA聚合的受控特性，这证实了氨基端基用于扩链的可用性。此外，通过从含赖氨酸的共聚物接枝L-谷氨酸苄酯NCA获得接枝共聚物。研究了由接枝物和相应的嵌段共聚物形成的凝胶。虽然通过光学显微镜观察嵌段共聚物互连的聚合物颗粒，但接枝共聚物形成开孔结构。
We have investigated the polymerization of various amino acid N-carboxyanhydrides (NCAs) at 0 degrees C. Detailed MALDI-ToF analysis of homopolymerizations of three amino acid NCAs clearly confirms that frequently occurring end-group termination and other side-reactions are absent at 0 degrees C. The polymerization is thus controlled and homo and copolypeptides with low polydispersities, around 1.1, were obtained for soluble polypeptides. MALDI-ToF contour plot analysis confirmed the randomness of the copolymers. The controlled character of the low temperature NCA polymerization was further verified by the successful block copolymer synthesis from polypeptide macroinitiators, which confirms the availability of the amino end-groups for chain extension. Moreover, graft copolymers were obtained by grafting of benzyl-L-glutamate NCA from lysine-containing copolymers. The formation of gels from the graft and corresponding block copolymers was investigated. While for the block copolymers interconnected polymer particles were observed by optical microscopy, the graft copolymers form an open cell structure.