School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
Nanoscale. 2019 Oct 10;11(39):18416-18425. doi: 10.1039/c9nr03797g.
As a widely studied photoactive antibacterial nanomaterial, the intrinsic antibacterial traits of graphitic carbon nitride (g-C3N4) as a two-dimensional nanomaterial have not been reported so far. Herein, nitrogen-plasma-treated g-C3N4 (N-g-C3N4) nanosheets and their influence on bactericidal characteristics are investigated. Bactericidal rates of more than 99% have been successfully achieved for 8 kinds of foodborne pathogenic bacteria by N-g-C3N4 with 8 h incubation in the dark. The achieved rates are percentage wise 10 times higher than those for pristine g-C3N4. Cell rupture caused by direct mechanical contact between g-C3N4 nanosheets and cell membranes is observed. X-ray photoelectron spectroscopy revealed a substantial loss of surface defects and nitrogen vacancies in N-g-C3N4. Molecular dynamics simulations further indicated that the largely sealed defects of N-g-C3N4 enhanced the electrostatic attraction between inherent pores and lipid heads; thus, further insertion of N-g-C3N4 was promoted, resulting in enhanced antibacterial activity. This study establishes novel fabrication and application strategies for carbon based antibacterial nanomaterials.
作为一种广泛研究的光活性抗菌纳米材料，石墨相氮化碳（g-C3N4）作为二维纳米材料的固有抗菌特性迄今尚未报道。在此，研究了氮等离子体处理的 g-C3N4（N-g-C3N4）纳米片及其对杀菌特性的影响。在黑暗中孵育 8 小时后，N-g-C3N4 成功地将 8 种食源性病原体的杀菌率提高到 99%以上。与原始 g-C3N4 相比，这一比率提高了 10 倍。观察到 g-C3N4 纳米片与细胞膜之间的直接机械接触导致细胞破裂。X 射线光电子能谱显示 N-g-C3N4 表面缺陷和氮空位大量损失。分子动力学模拟进一步表明，N-g-C3N4 的大封闭缺陷增强了固有孔和脂头部之间的静电吸引力；因此，促进了 N-g-C3N4 的进一步插入，从而提高了抗菌活性。本研究为基于碳的抗菌纳米材料建立了新的制造和应用策略。
