In this study, synthetic mimics of antimicrobial peptides based on poly(oxanorbornene) molecules (or PONs) were used to coat CdTe quantum dots (QDs). These PONs-CdTe QDs were investigated for their activity against Escherichia coli, a bacterium with antibiotic resistant strains. At the same time, the antibacterial activity of the PONs-CdTe QDs was compared to the antibacterial activity of free PONs and free CdTe QDs. The observed antibacterial activity of the PONs-CdTe QDs was additive and concentration dependent. The conjugates had a significantly lower minimum inhibitory concentration (MIC) than the free PONs and QDs, particularly for PONs-CdTe QDs which contained PONs of high amine density. The maximum activity of PONs-CdTe QDs was not realized by conjugating PONs with the highest intrinsic antibacterial activity (i.e., the lowest MIC in solution as free PONs), indicating that the mechanism of action for free PONs and PONs-CdTe QDs is different. Equally important, conjugating PONs to CdTe QDs decreased their hemolytic activity against red blood cells compared to free PONs, lending to higher therapeutic indices against E. coli. This could potentially enable the use of higher, and therefore more effective, PONs-QDs concentrations when addressing bacterial contamination, without concerns of adverse impacts on mammalian cells and organisms.

中文翻译：

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聚氧杂降冰片烯包覆的CdTe量子点作为抗菌剂

在这项研究中，基于聚氧杂降冰片烯分子（或PON）的抗菌肽的合成模拟物被用于包覆CdTe量子点（QD）。研究了这些PON-CdTe量子点对大肠杆菌的活性 ，一种具有抗生素抗性菌株的细菌。同时，将PONs-CdTe QDs的抗菌活性与游离PONs和游离CdTe QDs的抗菌活性进行了比较。所观察到的PONs-CdTe QD的抗菌活性是累加和浓度依赖性的。与游离的PON和QD相比，结合物的最低抑菌浓度（MIC）明显更低，特别是对于含有高胺密度PON的PONs-CdTe QD。PONs-CdTe QD的最大活性无法通过结合具有最高固有抗菌活性（即溶液中的MIC最低的游离PON）的PON来实现，这表明游离PON和PONs-CdTe QD的作用机理是不同的。同样重要大肠杆菌。解决细菌污染时，这可能潜在地使使用更高且因此更有效的PONs-QDs浓度，而无需担心对哺乳动物细胞和生物的不利影响。