再生纤维素基光敏抗菌纳米纤维膜的制备及表征

Preparation and Characterization of Photodynamic Antibacterial Nanofibrous Membranes Based on Regenerated Cellulose

利用静电纺丝技术制备纳米醋酸纤维素膜(CA),经高温热处理后碱液水解得再生纤维素(RC),然后以二乙烯三胺(DETA)为间隔臂接枝了原卟啉(PPIX),制备了PPIX接枝纳米纤维膜(RC-PPIX)。通过差示扫描量热分析、拉伸断裂仪、扫描电镜探究了CA热处理前、后及水解后的热学性能、力学性能及形貌变化。利用红外光谱、X射线光电子能谱表征了CA在反应过程中的化学结构变化,最后评价了RC-PPIX纤维膜对大肠杆菌的灭活作用。实验结果表明,热处理后的CA纳米纤维彼此熔合在一起,同时纳米纤维结构保持不变,纤维膜的力学强度显著提高;成功接枝制备了光敏抗菌型RC-PPIX纳米纤维膜,其对大肠杆菌的抗菌效果随着光照时间的延长,在氙灯光照30min时,其对大肠杆菌的灭活率可达99.99%。

Nanofibrous cellulose acetate membrane (CA) was prepared by electrospinning technique,after thermal treatment,the regenerated cellulose (RC) was obtained by fully hydrolysis of CA,then porphyrin conjugated nanofibrous membrane (RC-PPIX) was finally prepared by protoporphyrin IX (PPIX) covalent bonding via spacer arm,diethylenetriamine (DETA) linkage.The nanofibrous membranes were characterized by DSC,tensile tester and SEM to explore the thermal behavior,mechanical strength and surface morphology of the pristine CA,thermal treated CA and fully hydrolyzed CA.Chemical structure changes during the modification procedures were monitored by FT-IR and XPS.Finally,the antibacterial property of RC-PPIX was evaluated by Escherichia coli .The results demonstrate that,the mechanical strength of the thermal treated CA is improved significantly since the fiber is melted with each other and the nanofibrous structure is maintained at the same time ; the successfully prepared photoantibacterial nanofi-brous membrane exhibits better antibacterial property against E . coli with the illumination time increasing,the best inactivation rate is 99.999% when irradiated for 30min with Xenon lamp.