Broad-Spectrum Antibacterial Activity of Carbon Nanotubes to Human Gut Bacteria
Broad-Spectrum Antibacterial Activity of Carbon Nanotubes to Human Gut Bacteria
复制标题
碳纳米管对人体肠道细菌的广谱抗菌活性
DOI：
10.1002/smll.201202792
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发表时间：
2013-08-26
期刊：
影响因子：
13.3
通讯作者：
Feng, Weiyue
中科院分区：
文献类型：
--
作者：
Chen, Hanqing;Wang, Bing;Feng, Weiyue
碳纳米管 (CNT) 在制造、环境和生物医学应用以及食品和农业领域具有广阔的前景。此前的观察表明，碳纳米管具有抗菌活性；然而，碳纳米管对人类肠道微生物的影响尚未得到研究。在这里，碳纳米管对人体消化系统中常见的微生物具有抗菌活性。评估了嗜酸杆菌、青春芽孢杆菌、大肠杆菌、粪肠球菌和金黄色葡萄球菌。研究的细菌包括致病性和非致病性、革兰氏阳性和阴性以及球状和杆状菌株。在本研究中，碳纳米管，包括单壁碳纳米管（SWCNT，1-3 m）、短和长多壁碳纳米管（s-MWCNT：0.5-2 m；l-MWCNT：>50 m）和功能化多壁碳纳米管（羟基和羧基修饰，0.5-2 m），均具有广谱抗菌作用。值得注意的是，碳纳米管可以选择性地裂解人类肠道微生物的壁和膜，这不仅取决于碳纳米管的长度和表面官能团，还取决于细菌的形状。抗菌活性的机制与其对微生物壁和膜的裂解的直径依赖性刺穿和长度依赖性包裹有关，诱导细胞内成分DNA和RNA的释放，并允许细菌膜电位损失，从而证明细菌被完全破坏。薄且刚性的单壁碳纳米管比多壁碳纳米管对球形细菌具有更有效的壁/膜穿透能力。长的多壁碳纳米管可以包裹肠道细菌，增加与细菌壁接触的面积。这项工作表明，碳纳米管可能是肠道中广谱、高效的抗菌剂，选择性应用碳纳米管可以减少对益生菌的潜在危害。
Carbon nanotubes (CNTs) hold promise in manufacturing, environmental, and biomedical applications, as well as food and agricultural industries. Previous observations have shown that CNTs have antimicrobial activity; however, the impact of CNTs to human gut microbes has not been investigated. Here, the antibacterial activity of CNTs against the microbes commonly encountered in the human digestion systemL. acidophilus, B. adolescentis, E. coli, E. faecalis, and S. aureusare evaluated. The bacteria studied include pathogenic and non-pathogenic, gram-positive and negative, and both sphere and rod strains. In this study, CNTs, including single-walled CNTs (SWCNTs, 1-3 m), short and long multi-walled CNTs (s-MWCNTs: 0.5-2 m; l-MWCNTs: >50 m), and functionalized multi-walled CNTs (hydroxyl- and carboxyl-modification, 0.5-2 m), all have broad-spectrum antibacterial effects. Notably, CNTs may selectively lyse the walls and membranes of human gut microbes, depending on not only the length and surface functional groups of CNTs, but also the shapes of the bacteria. The mechanism of antibacterial activity is associated with their diameter-dependent piercing and length-dependent wrapping on the lysis of microbial walls and membranes, inducing release of intracellular components DNA and RNA and allowing a loss of bacterial membrane potential, demonstrating complete destruction of bacteria. Thin and rigid SWCNT show more effective wall/membrane piercing on spherical bacteria than MWCNTs. Long MWCNT may wrap around gut bacteria, increasing the area making contact with the bacterial wall. This work suggests that CNTs may be broad-spectrum and efficient antibacterial agents in the gut, and selective application of CNTs could reduce the potential hazard to probiotic bacteria.