载银壳聚糖接枝香草醛胶乳的制备及抗菌性

为了增强壳聚糖的抗菌活性和拓展其应用领域,在其基体中引入了纳米银粒子,并对其进行了接枝改性。采用微波辐射法将香草醛与壳聚糖接枝,然后用香草醛还原硝酸银,得到均匀分散于壳聚糖香草醛接枝物(CS-g-VA)胶乳中的纳米银粒子,即Ag/CS-g-VA复合胶乳。探讨了制备Ag/CS-g-VA复合胶乳的影响因素,并采用SEM,TEM,FTIR,XRD,UV-vis和TG-DSC等对其进行了结构和热性能表征。结果表明合成Ag/CS-g-VA的较理想条件:香草醛的质量分数为6.0%,CS-g-VA的质量分数为4.0%,硝酸银的浓度为0.20 mol/L。通过抗菌测试研究了Ag/CS-g-VA对大肠杆菌和枯草杆菌的抑制作用,结果显示Ag/CS-g-VA复合胶乳具有比单一壳聚糖抗菌剂更高效的抗菌性能。

Preparation and the antibacterial activity of silver-loaded Chitosan-grafted-vanillin sol

In order to enhance the antibacterial activity of chitosan and expand its application field, silver nanoparticles are introduced into the matrix, and the grafting modification is carried out. Chitosan grafted vanillin (CS-g-VA) is prepared with microwave-radiation method, and silver nitrate is reduced by vanillin, so that silver nanoparticles are separated evenly in CS-g-VA sol, which is Ag/CS-g-VA composite sol. The effects on the preparation of Ag/CS-g-VA composite sol are studied, and the structure and thermal property of the obtained composite sol are characterized by SEM, TEM, FTIR, XRD, UV-vis and TG-DSC. The experiment results show that the optimum conditions for the preparation of Ag/CS-g-VA are as following: Vanillin concentration of 6.0%, CS-g-VA concentration of 4.0%, and silver nitrate concentration of 0.20 mol/L. The inhibition of Ag/CS-g-VA composite sol against Escherichia coli and Bacillus subtilis is investigated through antibacterial tests. The results show that the antibacterial activity of Ag/CS-g-VA composite sol is more efficient than that of single CS materials.