【作者】 邵林军；

【导师】 吴健；

【作者基本信息】 浙江大学 ， 有机化学， 2010， 博士

【摘要】 聚肽作为蛋白质的模拟物,具有和蛋白质类似的化学组成和二级结构,是一类低毒、生物相容性好、容易被肌体和代谢的生物降解高分子,在生物医学领域如药物控释、组织工程等方面具有广泛的应用前景。本论文旨在通过α-氨基酸N-内酸酐(NCA)开环聚合合成聚肽,研究具有不同亲/疏水性及形貌的聚肽表面性能,以期对材料的表面性能有深入的了解,同时利用金属氨基卟啉的配位作用合成卟啉功能化的高分子量聚肽。具体研究内容如下:合成了烷基链分别为乙基、辛基、十二烷基和十八烷基的四种高分子量聚(γ-烷基-α,L-谷氨酸)(PALG),然后分别通过旋涂和静电纺丝法制备成致密膜和纤维膜。疏水性测试显示随着烷基侧链的增长,聚肽致密膜的疏水性不断增强,而纤维膜可以进一步放大相应致密膜表面的亲水或疏水性。同时发现PALG表面化学组成和形貌均显著影响其表面的血液相容性。采用电纺(喷)技术,通过调节聚(γ-十八烷基-α,L-谷氨酸酯)(PSLG)浓度制备了不同形貌的PSLG粗糙表面,研究了它们的疏水性能。证实颗粒膜表面具有更强的疏水性能,其中PSLG浓度为2 wt.%电喷颗粒形成的表面为低粘附力超疏水表面。另外,在3 wt.%的浓度下,在亲水性铝箔上电喷少量PSLG或者电喷PSLG含量为20～50wt.%的聚(γ-十二烷基-α,L-谷氨酸酯)(PDLG)/PSLG混合物溶液得到的粗糙表面是高粘附力超疏水表面,具有良好的液滴无损转移能力。以单氨基卟啉(APTPP)和二氨基卟啉(BAPDPP)及相应的金属氨基卟啉(MAPTPP,MBAPDPP)作为引发剂,引发γ-十八烷基-α,L-谷氨酸NCA(sLGNCA)开环聚合合成了卟啉功能化的PSLG。证实金属卟啉引发剂可以有效地消除SLGNCA聚合中的副反应,其中以CoAPTPP效果最为明显。进一步将这些卟啉化的PSLG电纺成纤维膜,其中APTPP和ZnAPTPP引发得到的PSLG制得的纤维形貌较差但具有很强的荧光;而CoAPTPP引发得到PSLG虽然可以制成良好形态的纤维,但纤维的荧光较弱。而含有APTPP的PSLG电纺膜对氯化氢具有良好的传感作用。更多还原

【Abstract】 Polypeptides and their derivatives are attractive polymers with potential applications in various fields such as tissue engineering and pharmaceutical materials.In this work, Poly(γ-alkyl-α,L-glutamate)s(PALG) were synthesized by ring-opening polymerization (ROP) ofα-amino acid N-carboxyanhydrides(NCA).Dense films and electrospun mats were carefully fabricated and studied to evaluate the effect of surface chemical composition and morphology on the surface properties.Furthermore,novel metalloporphyrins were used to initiate theγ-stearyl-α,L-glutamate NCA(SLGNCA) to synthesize porphyrinated poly(γ-stearyl-α,L-glutamate)(PSLG) with high molecular weight.The main results of this work are listed as follows:Dense films and electrospun mats of PALG with four different alkyl groups were prepared by spin casting and electrospinning,respectively.The hydrophobicities of dense films increased with the increment of the alkyl chain length while the microfiber structure of electrospun mats could enhance the hydrophobicity/hydrophobicity of PALG.It was found that the blood biocompatibility of these PALG surfaces were determined by both their surface chemical composition and morphology.By electrospinning/electrospraying at different concentrations,PSLG mats with different morphologies were prepared.It was found that the surface composed of beads had higher hydrophobicity than that of microfibers.No matter for the electrosprayed mats or electrospun mats,the hydrophobicity increased with the decrease of the bead or microfiber diameters.Low adhesive superhydrophobic surface was prepared by electrospraying PSLG at concentration of 3 wt.%for 60 min.By electrospraying PSLG at concentration of 3 wt.%for 5 min or PDLG/PSLG mixtures with PSLG content of 20～50 wt.%for 60 min on aluminium,high adhesive superhydrophobic surfaces can be obtained.5-(4-Aminophenyl)-10,15,25-triphenylporphyrin(APTPP) and corresponding metal APTPP(MAPTPP) were firstly applied as initiators for the ROP of SLGNCA.PSLGs synthesized by the metalloporphyrins had higher molecular weight than that synthesized by APTPP,especially for CoAPTPE PSLG synthesized with APTPP and ZnAPTPP can be electrospun into discontinus fiber mats with strong fluorescence intensities while PSLG synthesized with CoAPTPP can be electrospun into well-define mats but with low fluorescence intensities.更多还原