新型两性聚电解质型壳聚糖衍生物CMCTS-g-GDDA的制备及性能初探

Preparation and Preliminary Study on the Novel CMCTS-g-GDDA Polyampholyte

利用环氧丙基癸基二甲基氯化铵在羧甲基壳聚糖骨架上的接枝反应,制备了新型壳聚糖衍生物羧甲基壳聚糖-g-羟丙基十烷基二甲基氯化铵(CMCTS-g-GDDA)。CMCTS-g-GDDA具有两性聚电解质的结构特点,具有特殊的溶液黏度随pH值变化规律,在pH=2和pH=12处各出现一个黏度最大值,在pH=7附近达到等电点,黏度最小,在等电点处溶液黏度随离子强度的增大而增大。CMCTS-g-GDDA在弱酸性条件下对重金属离子具有良好的吸附效果,吸附量依Zn2+>Pb2+>Cd2+的顺序递减。CMCTS-g-GDDA溶液对金黄色葡萄球菌和谷草芽胞杆菌均具有良好的抑制效果,0.039%的CMCTS-g-GDDA溶液对上述两种细菌的抑菌圈直径分别为(0.91±0.17)cm和(1.00±0.21)cm。

Carboxymethyl chitosan-g-hydroxypropyl decylalkyl dimethyl ammonium chloride （CMCTS-g-GDDA） was prepared via graft reaction of glycidyl decylalkyl dimethyl ammonium chloride onto the chain of carboxymethyl chitosan. The properties of CMCTS-g-GDDA were studied,and it was found that CMCTS-g-GDDA shows the properties of polyampholyte. The viscosity of CMCTS-g-GDDA reaches the maximum value at pH=2 and pH=12,respectively,and the minimum value around pH=7,which is the isoelectric point of the CMCTS-g-GDDA polyampholyte. At the isoelectric point,the viscosity of the CMCTS-g-GDDA solution increases with the increase of the ionic strength. CMCTS-g-GDDA shows good adsorption characteristics to the heavy ions at the weak acidity condition and the adsorption capacities decrease according to the order of Zn^2＋〉Pb^2＋〉Cd^2＋. The antibacterial activities of CMCTS-g-GDDA against Staphylococcus aureus and Bacillus subtilis are distinct. Using 0.039% CMCTS-g-GDDA solution,the antimicrobial zone diameters of above bacteria are （0.91±0.17） cm and （1.00±0.21） cm,respectively.