Antibacterial activity of textile fibers containing poly(ethylene oxide-b-lactic acid) nanoparticles with incorporated essential oils

ABSTRACT In this study was evaluated the antibacterial activity of textile fibers containing poly (ethylene oxide-b-lactic acid) nanoparticles with incorporated essential oils. The developed system demonstrated antibacterial activity against Staphylococcus aureus, suggesting its potential use as antibacterial agent. Diblock copolymers based on a fixed PEO block (5kDa) and two different PLA segments (4.5 or 10kDa) were used. The morphology, encapsulation efficiency, blending interaction of essential oils (including lavender, tea tree, thyme, cloves, cedar and lemon grass) and polymer and the release kinetics of the active agent in the nanoparticles. The hydrodynamic radius of the nanoparticles determined by light scattering was affected by the size of the poly(lactic acid) block. The in vitro release suggests that the polymeric barrier is able to control the oil release. Antibacterial activity was more effective in textiles with randomly arranged fibers. In agreement with studies from the literature, nanoparticles obtained from copolymers with lower PLA molar mass favored the release of the essential oil mixture. The incorporation process of the essential oils in the textile fibers proved to be efficient, suggesting viability regarding the use of this system in the antibacterial control. The developed systems offer a new strategy for controlled release with antibacterial activity and suggesting a potential application in the footwear industry.

摘要：本研究评估了负载精油的聚（环氧乙烷-b-乳酸）(poly(ethylene oxide-b-lactic acid))纳米颗粒复合纺织纤维的抗菌活性。本研究开发的该体系对金黄色葡萄球菌(Staphylococcus aureus)表现出抗菌活性，提示其具备作为抗菌剂的应用潜力。实验采用了基于固定分子量聚环氧乙烷(PEO)链段（5kDa）与两种不同分子量聚乳酸(PLA)链段（4.5或10kDa）的二嵌段共聚物。本研究考察了纳米颗粒的形貌、包封率、精油（涵盖薰衣草、茶树、百里香、丁香、雪松及柠檬草精油）与聚合物的共混相互作用，以及活性成分的释放动力学。通过光散射法测得的纳米颗粒流体力学半径，受聚乳酸(PLA)链段分子量的影响。体外释放实验结果表明，该聚合物屏障可实现精油释放的可控调节。纤维无规排布的纺织材料展现出更优异的抗菌活性。与已有文献研究结果一致，采用较低分子量PLA链段的共聚物制备的纳米颗粒，更利于精油混合体系的释放。将精油负载至纺织纤维中的工艺被证实具有高效性，提示该体系用于抗菌调控具备应用可行性。本研究开发的体系为具备抗菌活性的可控释放技术提供了全新思路，并有望在制鞋产业中实现应用。