DataSheet1_Antimicrobial properties of hindered amine light stabilizers in polymer coating materials and their mechanism of action.pdf

UV-stabilizers are a class of additives that provide extended polymer resistance to UV-degradation, but have also been suggested to have antimicrobial activity, potentially preventing the spread of pathogens, and inhibiting microbial-induced biodegradation. In this work, we incorporated different UV-stabilizers, a hindered amine light stabilizer (HALS), Tinuvin 770 DF and Tinuvin PA 123, or a hybrid HALS/UV-absorber, Tinuvin 5151, in polyurethane formulations to produce lacquer-films, and tested their antimicrobial activity against Staphylococcus aureus (methicillin-resistant and -sensitive strains), Escherichia coli and Candida albicans. Lacquer-films incorporated with Tinuvin 770 DF showed strong antimicrobial performance against bacteria and fungi, while maintaining cytocompatibility. The mechanism of action revealed a positive relationship between Tinuvin 770 DF concentration, microbial death, and reactive nitrogen species (RNS), suggesting that RNS produced during autoxidation of Tinuvin 770 DF is responsible for the antimicrobial properties of this UV-stabilizer. Conversely, lacquer-films incorporated with Tinuvin 5151 or Tinuvin PA 123 exhibited no antimicrobial properties. Collectively, these results highlight the commercial potential of Tinuvin 770 DF to prevent photo- and biodegradation of polymers, while also inhibiting the spread of potentially harmful pathogens. Furthermore, we provide a better understanding of the mechanism underlying the biocidal activity of HALS associated to autooxidation of the amine group.

紫外线稳定剂（UV-stabilizers）是一类可延长聚合物抗紫外线降解性能的添加剂，现有研究表明其兼具抗菌活性，可潜在阻断病原体传播并抑制微生物诱导的生物降解。本研究将不同种类的紫外线稳定剂——受阻胺光稳定剂（hindered amine light stabilizer, HALS）Tinuvin 770 DF、Tinuvin PA 123，以及混合型受阻胺光稳定剂/紫外线吸收剂Tinuvin 5151——添加至聚氨酯配方中以制备漆膜，并针对耐甲氧西林与甲氧西林敏感金黄色葡萄球菌（Staphylococcus aureus）、大肠杆菌（Escherichia coli）以及白色念珠菌（Candida albicans）测试了其抗菌活性。添加了Tinuvin 770 DF的漆膜展现出针对细菌与真菌的强效抗菌性能，同时维持了细胞相容性。研究揭示的作用机制表明，Tinuvin 770 DF的浓度与微生物死亡率以及活性氮物种（reactive nitrogen species, RNS）之间存在正相关关系，这表明Tinuvin 770 DF自氧化过程中产生的活性氮物种是该紫外线稳定剂抗菌特性的成因。与之相反，添加了Tinuvin 5151或Tinuvin PA 123的漆膜未表现出抗菌性能。综上，本研究结果凸显了Tinuvin 770 DF在防止聚合物光降解与生物降解方面的商业化应用潜力，同时还能抑制潜在有害病原体的传播。此外，本研究进一步阐明了与胺基自氧化相关的受阻胺光稳定剂杀菌活性的潜在机制。