Silver nanoparticles incorporated into nanostructured biopolymer membranes produced by electrospinning: a study of antimicrobial activity

abstract This study examines the antimicrobial activity of silver nanoparticles incorporated into nanostructured membranes made of cellulose acetate (CA) and blends of chitosan/poly-(ethylene oxide, CTS/PEO) and prepared by electrospinning. The formation of chemically synthesized Ag nanoparticles (AgNPs) was monitored by UV-visible spectroscopy (UV-Vis) and characterized by transmission electron microscopy (TEM). The size distribution of the AgNPs was measured by dynamic light scattering (DLS), with an average size of approximately 20 nm. The presence of AgNPs on the surface of electrospun nanofibers was observed by field emission electron microscopy (FEG) and confirmed by TEM. The antimicrobial activity of AgNPs incorporated into nanostructured membranes made of CA and CTS/PEO electrospun nanofibers was evaluated in the presence of both Gram-positive bacteria, such as Staphylococcus aureus ATCC 29213 and Propionibacterium acnes ATCC 6919, and Gram-negative bacteria, such as Escherichia coli ATCC 25992 and Pseudomonas aeruginosa ATCC 17933. Microbiological results showed that the presence of AgNPs in CA and CTS/PEO nanostructured membranes has significant antimicrobial activity for the Gram-positive bacteria Escherichia coli and Propionibacterium acnes.

摘要 本研究探讨了掺入银纳米颗粒的纳米结构膜的抗菌活性，该类膜由醋酸纤维素（Cellulose Acetate, CA）以及壳聚糖/聚环氧乙烷（Chitosan/Poly-(ethylene oxide), CTS/PEO）共混物制备，制备工艺为静电纺丝（Electrospinning）。本研究通过紫外-可见分光光度法（UV-Vis）对化学合成的银纳米颗粒（AgNPs）的形成过程进行监测，并借助透射电子显微镜（Transmission Electron Microscopy, TEM）完成表征。采用动态光散射（Dynamic Light Scattering, DLS）测定了AgNPs的粒径分布，其平均粒径约为20 nm。通过场发射电子显微镜（Field Emission Electron Microscopy, FEG）观察到静电纺纳米纤维表面存在AgNPs，并经TEM验证了该结果。本研究针对负载于CA及CTS/PEO静电纺纳米纤维构成的纳米结构膜中的AgNPs，对两类受试细菌的抗菌活性进行了评估，受试菌株包括革兰氏阳性菌（Gram-positive bacteria）：金黄色葡萄球菌（Staphylococcus aureus）ATCC 29213与痤疮丙酸杆菌（Propionibacterium acnes）ATCC 6919，以及革兰氏阴性菌（Gram-negative bacteria）：大肠埃希菌（Escherichia coli）ATCC 25992与铜绿假单胞菌（Pseudomonas aeruginosa）ATCC 17933。微生物学实验结果表明，掺入CA与CTS/PEO纳米结构膜中的AgNPs对大肠埃希菌与痤疮丙酸杆菌均具有显著的抗菌活性。