生物黏附材料壳聚糖的黏附性能

Mucoadhesive property of chitosan

目的:考察壳聚糖与黏蛋白的相互作用,评价壳聚糖黏附性能的影响因素。方法:于2006-07/12在中国科学院大连化学物理研究所生物医用材料工程实验室完成。将壳聚糖溶液与黏蛋白溶液混合,用紫外分光光度计测定溶液混合前后紫外吸收值的变化,表征壳聚糖的黏附性能。①调节反应溶液的pH值(1.0,3.0,5.0),考察环境pH对壳聚糖黏附性能的影响。②改变反应温度(4,25,37℃),考察环境温度对壳聚糖黏附性能的影响。③选择不同相对分子质量(48000,124000,230000)的壳聚糖,考察壳聚糖相对分子质量对其黏附性能的影响。④选择不同脱乙酰度(56%,67%,97%)的壳聚糖,考察壳聚糖脱乙酰度对其黏附性能的影响。⑤使用不同种类(I-S型及Ⅲ型)黏蛋白,考察黏蛋白中唾液酸含量对壳聚糖黏附性能的影响。结果:①环境介质pH由1.2升至5.0时,壳聚糖黏附性能随之显著升高。②壳聚糖黏附性能随着温度的升高而显著增强。③壳聚糖相对分子质量对于壳聚糖黏附无显著影响。④壳聚糖脱乙酰度增加,其黏附性能显著增强。⑤I-S型黏蛋白与壳聚糖的作用较之Ⅲ型黏蛋白与壳聚糖的相互作用明显增强。结论:壳聚糖的黏附受环境pH、温度、壳聚糖及黏蛋白两种分子电荷密度的显著影响;在酸性环境下增大环境pH值、升高环境温度、增加壳聚糖的脱乙酰度和增加黏蛋白中唾液酸的含量,均有利于壳聚糖的黏附。

AIM： To investigate the interaction between chitosan and mucin, and evaluate the influencing factors of the mucoadhesive property of chitosan. METHODS： The experiment was done in Laboratory of Biomedical Material Engineering, Dalian Institute of Chemical Physics in the Chinese Academy of Science between July and December in 2006. The mucoadhesive property of chitosan was evaluated by studying interaction between chitosan and mucin in solution with UV spectrophotometry①The pH value of medium was adjusted （1.0, 3.0 and 5.0） to study the influence of pH to mucoadhesive property of chitosan.②The temperature of medium was adjusted （4, 25 and 37 %） to study the influence of temperature on mucoadhesive property of chitosan.③The influence of molecular weight （MW） of chitosan （48 000, 124 000 and 230 000） to its mucoadhesive property was studied.④The influence of deactylation degree （DD） of chitosan （56%, 67% and 97%） was studied likewise.⑤Different types of mucin were used to study the influence of sialic acid concentration to mucoadhesive property of chitosan. RESULTS; ①The interaction between chitosan and mucin was enhanced as the pH value of medium increased from 1.2 to 5.0. ②The mucoadhesive property of chitosan increased with an increasing of temperature. ③The influence of chitosan＇s MW to mucoadhesion was not significant; ④With an increasing DD of chitosan, the interaction between chitosan and mucin was enhanced significantly; ⑤A greater interaction with chitosan was found with a high sialic content of the mucin （type I-S）. CONCLUSION. The pH value, temperature, charge density of chitosan and mucin significantly affect the interaction between chitosan and mucin, which can be enhanced by increasing pH value of medium, temperature, DD of chitosan and sialic acid concentration of mucin.