Abstract The emergent need for new treatment methods for multi-drug resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) has focused attention on novel potential tools like nanoparticles (NPs). In the present study, a drug-free cationic nanoparticles (CNPs) system was developed and its anti-MRSA effects were firstly investigated. The results showed that CNPs (261.7 nm, 26.1 mv) showed time- and concentration-dependent activity against MRSA growth, killing ∼ 90% of planktonic bacterial cells in 3 h at 400 μg ml−1, and completely inhibiting biofilm formation at 1000 μg ml−1. Moreover, CNPs at 400 μg ml−1 reduced the minimum inhibitory concentration (MIC) of vancomycin on inhibition of planktonic MRSA growth (∼ 25%) and biofilm formation (∼ 50%). The CNPs–bacteria interaction force was up to 22 nN. Overall, these data suggest that CNPs have a good potential in clinical applications for the prevention and treatment of MRSA infection.

中文翻译：

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阳离子聚（D，L-丙交酯-共-乙交酯）纳米颗粒抑制耐甲氧西林金黄色葡萄球菌（MRSA）生物膜

摘要 对耐甲氧西林金黄色葡萄球菌 (MRSA) 等多重耐药病原体的新治疗方法的迫切需求已将注意力集中在纳米粒子 (NPs) 等新型潜在工具上。在本研究中，开发了一种不含药物的阳离子纳米颗粒 (CNPs) 系统，并首先研究了其抗 MRSA 的作用。结果表明，CNPs (261.7 nm, 26.1 mv) 对 MRSA 生长显示出时间和浓度依赖性活性，在 400 μg ml-1 浓度下在 3 小时内杀死约 90% 的浮游细菌细胞，并在 1000 μg 浓度下完全抑制生物膜形成毫升-1。此外，400 μg ml-1 的 CNP 降低了万古霉素对浮游 MRSA 生长（~25%）和生物膜形成（~50%）抑制的最小抑制浓度（MIC）。CNPs-细菌相互作用力高达22 nN。全面的，