文丘里管空化强化离子交联法制备壳聚糖抗菌微粒

Preparation of chitosan antibacterial microparticles via ionic cross-linking intensified by Venturi-tube based hydrodynamic cavitation

以甲基异噻唑啉酮(methylisothiazolinone,MIT)为模型抑菌剂,采用基于文丘里管的水力空化强化离子交联法制备壳聚糖抗菌微粒,考察不同配方和工艺条件对平均粒径和包封率的影响,并和传统机械搅拌制备进行比较。结果表明,三聚磷酸钠(sodium tripolyphosphate, TPP)与壳聚糖质量比是影响平均粒径大小的关键因素,且当二者质量比为2:15～6:15,文丘里管空化可稳定制备得到微粒;优化工艺条件为:空化入口压力0.2MPa、空化时间20min、壳聚糖质量浓度3.0 g×L^(-1)、TPP与壳聚糖质量比6:15、MIT浓度0.5 mmol×L^(-1);此时制备的微粒分散性好、形态圆整,且粒度分布窄,平均粒径为329.4 nm,包封率为(62.3±2.57)%,和传统机械搅拌相比,平均粒径减小20.5%,包封率提高17.7%以上。文丘里管空化适用于强化离子交联法制备壳聚糖抗菌微粒。

Chitosan microparticles loaded with a model antimicrobial agent methylisothiazolinone(MIT)was prepared via ionic cross-linking which was intensified by Venturi tube-based cavitation.Effects of ingredients and process conditions on mean particle size and encapsulation efficiency were studied and the performance was compared with that of mechanical agitation.The results show that the mass ratio of sodium tripolyphosphate(TPP)and chitosan is a critical factor in determining mean particle size,and microparticles can be stably obtained by cavitation with mass ratio of 2:15~6:15.The optimal preparation conditions are:cavitation inlet pressure=0.2 MPa,cavitation time=20 min,chitosan mass concentration=3.0 g·L^-1,mass ratio of TPP and chitosan=6:15 and MIT concentration=0.5 mmol·L^-1.The obtained microparticles show good dispersion,round shape and narrow size distribution with mean particle size=329.4 nm.The encapsulation efficiency is(62.3±2.57)%.Compared with the microparticles prepared by mechanical agitation,the mean particle size is decreased by at least 20.5%and the encapsulation efficiency is increased by at least 17.7%.The Venturi tube-based cavitation is suitable for intensification in the preparation of chitosan antibacterial microparticles.