胶原蛋白改性聚乳酸的制备和性能研究

发布时间：2018-03-29 04:19

本文选题：聚乳酸　切入点：胶原蛋白　出处：《山东轻工业学院》2012年硕士论文

【摘要】：聚乳酸（Poly(lactic acid)，PLA）由于具有良好的生物可降解性、生物相容性和力学性能，在医用手术缝合线、注射用胶囊、微球等医学领域得到广泛应用和认可。但聚乳酸亲水性较差，降低了其细胞相容性。另外聚乳酸相对分子量分布较宽，降解周期难以控制，降解中会导致局部酸性积累。因此，克服聚乳酸单一材料的性能缺陷，使其能更好的满足某些医学领域的应用需求就显得尤为重要。本文以自制PLA为原料，以酰氯化为主，使用PCl_5、PCl_3作为酰氯化试剂，将PLA末端的羧酸基-COOH酰氯化成-COCl，再将胶原蛋白引入到PLA整体中，制备出胶原蛋白改性聚乳酸材料CPLA。本文采用红外光谱（FTIR）、荧光光谱、光电子能谱（XPS）、差示扫描量热仪（DSC）以及茚三酮显色分析等方法对改性聚乳酸进行了表征，红外谱图分析显示CPLA中出现了仲酰胺以及伯胺的N-H特征吸收峰，以PCl_5法制备的CPLA的特征峰最明显；荧光光谱显示采用异硫氰酸荧光素（FITC）标记的CPLA在在510～550nm之间有较强的发射光谱，在450～500nm之间也有激发光谱，而FITC标记的PLA则没有吸收；XPS显示，在CPLA中检测到了N元素，而PLA中没有；DSC分析表明，CPLA只有一个玻璃化转变温度；这些结论都表明了胶原蛋白已经成功接枝到PLA中。亲水性测试结果显示，相对于纯PLA，CPLA的接触角（61°）有所减小，而吸水率（3.49%）要明显高于纯PLA。通过降解过程特性粘度变化测试，发现，前三周CPLA和PLA的降解趋势基本相同，但是从第四周开始CPLA的降解趋势明显要比PLA的稳定、平缓。同时，降解过程失重率测试也说明，CPLA降解趋势平稳。而CPLA在降解过程中并未出现酸催化自加速降解行为。3T3细胞相容性测试显示，通过显微镜形态观察，发现CPLA基底上细胞多呈短梭形、三角形，，细胞密度高，并且大部分连接成片，细胞的生长状况要明显好于PLA组和玻璃组。并且细胞增殖曲线也显示，在CPLA上细胞增殖速率始终明显高于PLA组。本文研究结果说明：经PCl_5法制备出的CPLA的亲水性要明显好于PLA，降解过程平稳，没有出现酸致自催化加速降解的现象。并且CPLA表现出较为出色细胞相容性。因此，本文通过酰氯化制备出的CPLA有望成为一种新型医用高分子材料。
[Abstract]:Because of its good biodegradability, biocompatibility and mechanical properties, PLA has been widely used and recognized in medical fields such as surgical suture, injection capsules, microspheres and so on, but the hydrophilicity of polylactic acid is poor. In addition, the relative molecular weight distribution of polylactic acid is relatively wide, the degradation cycle is difficult to control, and the degradation will lead to local acid accumulation. So that it can better meet the needs of some medical applications is particularly important. In this paper, PLA was used as raw material, acyl chlorination was used as the main material, PCL _ (5) / PCL _ (3) was used as acyl chlorination reagent, carboxylic acid -COOH acyl chloride at the end of PLA was formed into -COCl, and collagen was introduced into PLA to prepare collagen modified poly (lactic acid) material. In this paper, the modified polylactic acid was characterized by FTIR, fluorescence, photoelectron spectroscopy (XPS), differential scanning calorimetry (DSC) and color analysis of ninhydrin. Infrared spectrum analysis showed that the N-H characteristic absorption peaks of paramide and primary amine appeared in CPLA, the characteristic peaks of CPLA prepared by PCl_5 method were the most obvious, and the fluorescence spectra showed that CPLA labeled with fluorescein isothiocyanate had a strong emission spectrum between 510~550nm. There were also excitation spectra between 450~500nm and PLA labeled with FITC. The N element was detected in CPLA, but there was only one glass transition temperature in PLA. These results indicate that collagen has been successfully grafted into PLA. The results of hydrophilic test showed that the contact angle (61 掳) of CPLA was decreased, but the water absorption was 3.49), which was obviously higher than that of pure PLA.The degradation trend of CPLA and PLA in the first three weeks was basically the same, by testing the change of intrinsic viscosity during the degradation process. But from the fourth week on, the degradation trend of CPLA was obviously more stable and gentle than that of PLA. At the same time, The weight loss rate test also showed that the degradation trend of CPLA was stable, but the acid-catalyzed autoaccelerated degradation behavior. 3T3 cell compatibility test showed that the cells on CPLA substrate were mostly short spindle shape. The cell density was high and most of the cells were connected into pieces. The growth status of the cells was obviously better than that of PLA and glass groups. The cell proliferation curve also showed that the cell proliferation rate in CPLA was always higher than that in PLA group. The results show that the hydrophilicity of CPLA prepared by PCl_5 method is obviously better than that of CPLA, the degradation process is stable, and there is no acid-induced autocatalytic accelerated degradation phenomenon, and CPLA has excellent cytocompatibility. In this paper, CPLA prepared by acyl chlorination is expected to be a new kind of medical polymer material.
【学位授予单位】：山东轻工业学院
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R318.08

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