Abstract Pseudomonas aeruginosa is an opportunistic Gram-negative pathogen often associated with biofilm infections. This study evaluated the capacity for biofilm destruction of a novel combination of cationic polymer micelles formed from poly(2-(dimethylamino)ethyl methacrylate)-b-poly(ε-caprolactone)-b-poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA-PCL-PDMAEMA) triblock copolymer either alone, or loaded with silver nanoparticles (M_AgNPs). Pre-formed P. aeruginosa biofilms were incubated with either blank micelles, AgNO3, or M_AgNPs. Biofilm biomass (crystal violet assay), metabolic activity (Alamar blue reduction), structure (SEM) and viability (CLSM after Live/Dead staining, or plating for CFU) were checked. The results showed that the micelles alone loosened the biofilm matrix, and caused some alterations in the bacterial surface. AgNO3 killed the bacteria in situ leaving dead biofilm bacteria on the surface. M_AgNPs combined the two types of activities causing significant biofilm reduction, and alteration and death of biofilm bacteria. Therefore, the applied PDMAEMA-based micelles appear to be a successful candidate for the treatment of P. aeruginosa biofilm infections.

中文翻译：

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含银纳米粒子的阳离子聚合物胶束破坏铜绿假单胞菌预形成的生物膜

摘要 铜绿假单胞菌是一种机会性革兰氏阴性菌，常与生物膜感染有关。本研究评估了由聚（2-（二甲氨基）甲基丙烯酸乙酯）-b-聚（ε-己内酯）-b-聚（2-（二甲氨基）乙基甲基丙烯酸乙酯）形成的新型阳离子聚合物胶束组合对生物膜破坏的能力(PDMAEMA-PCL-PDMAEMA) 三嵌段共聚物，可以单独使用，也可以负载银纳米颗粒 (M_AgNPs)。预先形成的铜绿假单胞菌生物膜与空白胶束、AgNO3 或 M_AgNPs 一起孵育。检查生物膜生物量（结晶紫测定）、代谢活性（阿拉玛蓝还原）、结构（SEM）和活力（活/死染色后的 CLSM，或 CFU 电镀）。结果表明，胶束单独使生物膜基质松散，并引起细菌表面的一些改变。AgNO3 原位杀死细菌，在表面留下死生物膜细菌。M_AgNPs 结合了两种类型的活性，导致生物膜显着减少，生物膜细菌改变和死亡。因此，应用的基于 PDMAEMA 的胶束似乎是治疗铜绿假单胞菌生物膜感染的成功候选者。