Role of Size and Shape on Biofilm Eradication for Nitric Oxide-Releasing Silica Nanoparticles
Role of Size and Shape on Biofilm Eradication for Nitric Oxide-Releasing Silica Nanoparticles
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DOI：
10.1021/am402618w
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发表时间：
2013-10-09
影响因子：
9.5
通讯作者：
Schoenfisch, Mark H.
中科院分区：
文献类型：
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作者：
Slomberg, Danielle L.;Lu, Yuan;Schoenfisch, Mark H.
一氧化氮(NO)是一种反应性自由基，已被证明在消除细菌生物膜方面有效，并降低了培养抗菌素耐药性的风险。在这里，我们评估了NO释放的二氧化硅纳米颗粒对革兰氏阴性铜绿假单胞菌和革兰氏阳性金黄色葡萄球菌生物被膜的疗效与颗粒大小和形状的关系。三种大小的释放NO的二氧化硅纳米颗粒(即14、50和150 nm)具有相同的总NO释放量(类似于0.3微克分子/毫克)，用来研究抗生物膜的清除与大小的关系。为了观察颗粒形状对生物被膜杀灭的影响，我们改变了释放NO的二氧化硅颗粒的长径比从1到8，同时保持恒定的颗粒体积(类似于0.02µm(3))和NO释放总量(类似于0.7µmol/mg)。大小和长径比增大的一氧化氮释放颗粒对铜绿假单胞菌和金黄色葡萄球菌生物被膜都有更好的抑制作用，其中革兰氏阴性菌对NO的敏感性最高。为了进一步了解这些纳米颗粒的性质对NO介导的抗菌活性的影响，我们用共聚焦显微镜观察了细胞内NO浓度和细胞死亡。与大颗粒(50 nm和150 nm)相比，较小的NO释放颗粒(14 Nm)表现出更好的NO传递和增强杀菌作用。同样，事实证明，棒状NO释放颗粒比球形颗粒更有效地输送NO，并在整个生物膜中诱导更大的抗菌作用。
Nitric oxide (NO), a reactive free radical, has proven effective in eradicating bacterial biofilms with reduced risk of fostering antibacterial resistance. Herein, we evaluated the efficacy of NO-releasing silica nanoparticles against Gram-negative Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus biofilms as a function of particle size and shape. Three sizes of NO-releasing silica nanoparticles (i.e., 14, 50, and 150 nm) with identical total NO release (similar to 0.3 mu mol/mg) were utilized to study antibiofilm eradication as a function of size. To observe the role of particle shape on biofilm killing, we varied the aspect ratio of the NO-releasing silica particles from 1 to 8 while maintaining constant particle volume (similar to 0.02 mu m(3)) and NO-release totals (similar to 0.7 mu mol/mg). Nitric oxide-releasing particles with decreased size and increased aspect ratio were more effective against both P. aeruginosa and S. aureus biofilms, with the Gram-negative species exhibiting the greatest susceptibility to NO. To further understand the influence of these nanoparticle properties on NO-mediated antibacterial activity, we visualized intracellular NO concentrations and cell death with confocal microscopy. Smaller NO-releasing particles (14 nm) exhibited better NO delivery and enhanced bacteria killing compared to the larger (50 and 150 nm) particles. Likewise, the rodlike NO-releasing particles proved more effective than spherical particles in delivering NO and inducing greater antibacterial action throughout the biofilm.