Department of Chemical and Biomolecular Engineering, National University of Singapore , Kent Ridge, Singapore 117576.
ACS Appl Mater Interfaces. 2017 Sep 6;9(35):29515-29525. doi: 10.1021/acsami.7b07700. Epub 2017 Aug 22.
Bacteria-contaminated inanimate surfaces within hospitals and clinics result in transmission of pathogens via direct or indirect contact, leading to increased risk of healthcare-associated infections (HAI). The use of antibacterial coatings is a potential way of reducing the bacterial burden, but many surfaces such as instrument panels and monitors necessitate the coatings to be transparent while being highly antibacterial. In this work, silica nanoparticles (SiO NPs) were first grown over a layer of acrylated quaternized chitosan (AQCS) covalently immobilized on commercially available transparent poly(vinyl fluoride) (PVF) films. The SiO NPs then served as nanoreservoirs for adsorption of copper ions. The coated PVF films were transparent and reduced viable bacterial count by ∼99% and 100%, when incubated with a bacteria-loaded droplet for 60 and 120 min, respectively. The killing efficacy of these coatings, after wiping 100 times, with a deionized water-wetted cloth was reduced slightly to 97-98%. The stability of these coatings can be further improved with the deposition of another layer of cationic quaternized chitosan (QCS) over the negatively charged SiO NP layer, wherein the coatings maintained ∼99% killing efficacy even after 100 wipes. These coatings showed no significant toxicity to mammalian cells and, hence, can potentially be used in a clinical setting for reducing HAI.
医院和诊所中被细菌污染的无生命表面会通过直接或间接接触导致病原体传播,从而增加与医疗保健相关的感染(HAI)的风险。使用抗菌涂层是减少细菌负担的一种潜在方法,但许多表面,如仪器面板和监视器,需要涂层透明且具有高度抗菌性。在这项工作中,首先在商业可得的透明聚偏氟乙烯(PVF)薄膜上通过接枝共聚固定的季铵化壳聚糖(AQCS)层上生长二氧化硅纳米颗粒(SiO NPs)。然后,SiO NPs 充当吸附铜离子的纳米储库。当用负载细菌的液滴滴附 60 和 120 分钟时,涂层的 PVF 薄膜是透明的,并且将活菌数分别减少了约 99%和 100%。用去离子水润湿的布擦拭 100 次后,这些涂层的杀菌效果略有降低,降至 97-98%。通过在带负电荷的 SiO NP 层上沉积另一层阳离子季铵化壳聚糖(QCS),可以进一步提高这些涂层的稳定性,其中即使经过 100 次擦拭,涂层仍保持约 99%的杀菌效果。这些涂层对哺乳动物细胞没有明显的毒性,因此可能在临床环境中用于减少 HAI。