短肽RADAl6-1A组装纤维长度与止血关系研究

目的：RADAl6—1为人工设计的含16个氨基酸残基短肽，可自组装形成稳定的长纤维水凝胶，并具有外科止血功能。主要探讨RADAl6—1自组装成长纤维的时间动力学变化特点及其与止血功能之间的关系。，方法：利用化学合成法人工合成RADAl6—1短肽，制备成短肽溶液，并经超声处理通过圆二色谱分析水溶液中短肽分子的结构特征；通过原子力显微镜扫描分析超声处理前后短肽材料的表面特征；利用流变力学分析短肽由单体自组装成长纤维的时间动力学变化特点。建立脊髓损伤出血和肝创伤出血动物模型，研究RADAl6—1自组装成纤维的长度与止血功能的关系。结果：圆二色谱结果表明，超声前后溶液中短肽均为β-折叠特征；原子力显微镜扫描分析发现RADAl6—1可自组装成长度（786．34±96．54）nm的长纤维，且被超声折断的纤维具有自组装成长纤维的能力；流变力学分析结果显示短肽RADAl6—1单体自组装成长纤维的过程与时间呈正相关，动物止血实验结果显示RADAl6—1自组装纤维长度与完全止血所需时间呈负相关。结论：短肽RADAl6—1溶液可迅速原位水凝胶化成长纤维状，并能在外科手术中作为止血剂迅速止血．

Relationship Between Fiber Length and Hemostasis of Self-assembled Peptide RADA16-1

Objective： A self-assembled small peptide RADARADARADARADA （RADA 16-1 ） can form a long fiber hydrogel, which has the function of surgical hemostasis, to explore the long fi- ber assemble dynamics and hemostasis mechanism of peptide RADA16-1. Methods：Through cireu- lar dichroism spectrum, atomic force characterization and rheological mechanics analysis, kinetics of long fiber self-assemble had been studied. Hemostatic models of spinal cord injury and liver trau- ma were established to study the effect of blooding control. Results ： The results of circular dichroism spectrum indicated that RADA16-1 in solution was beta folding characteristics both before and after ultrasound. The resuhs of atomic force characterization and theological mechanics analysis showed that RADA16-1 can self-assemble into long fiber which length was about （786. 34 ± 96.54） nm, and the long fiber assembled process of RADA16-1 was positively associated with time after ultra- sound. Meanwhile, a negative correlation was detected between the long fiber length and the bleed- ing time in animal models. Conclusion： The small peptide RADA16-1 solution can rapidly situ hy- drogelize to long fiber form, can be used in surgery as hemostatic.