Jo Jin Hyoung, Kim Hyun-Chul, Huh Seong, Kim Youngmee, Lee Do Nam
Department of Chemistry and Protein Research Centre for Bio-Industry, Hankuk University of Foreign Studies, Yongin 17035, Republic of Korea.
Institute of Nano-Bio Technology and Department of Chemistry and Nano Science, Ewha Womans University, Seoul 03760, Republic of Korea.
Dalton Trans. 2019 Jun 21;48(23):8084-8093. doi: 10.1039/c9dt00791a. Epub 2019 Apr 29.
Metal-organic frameworks (MOFs) can be utilized as antibacterial agents due to their effective antibacterial activities. Four three-dimensional (3D) Cu-MOFs formulated as [Cu(Glu)(μ-L)]·x(HO) (Glu is glutarate, and L is bpy = 4,4'-bipyridine (1), bpa = 1,2-bis(4-pyridyl)ethane (2), bpe = 1,2-bis(4-pyridyl)ethylene (3), and bpp = 1,2-bis(4-pyridyl)propane (4)) were synthesized by hydrothermal reactions or modified literature methods. Their solid-state structures were slightly modified to increase their hydrolytic stabilities in aqueous solution. Despite the seemingly sufficient void spaces in all the solvent-free MOFs, only the thermally activated form of MOF 2 displayed selective gas uptake ability for CO over N and H. The antibacterial activities of the four Cu-MOFs, 1, 2, 3, and 4, were investigated by determining their minimal bactericidal concentration (MBC) values against five strains of bacteria, including E. coli, S. aureus, K. pneumonia, P. aeruginosa, and MRSA, which can be easily met in our daily surrounding environments. Although these Cu-MOFs were found to be structurally very stable in aqueous medium during antibacterial activity tests, they exhibited excellent antibacterial activities against all five kinds of bacteria, including Gram-positive bacteria (S. aureus and MRSA) and Gram-negative bacteria (E. coli, K. pneumonia, and P. aeruginosa), with very low MBCs. The robust 3D frameworks with surface active metal sites rather than the small amount of leached Cu ions may participate more strongly in inactivating various kinds of bacteria and reduce potential cytotoxicity mainly caused by leached metal ions.
金属有机框架材料（MOFs）因其有效的抗菌活性可被用作抗菌剂。通过水热反应或改进的文献方法合成了四种三维（3D）铜基金属有机框架材料，其化学式为[Cu(Glu)(μ-L)]·x(HO)（Glu为戊二酸，L为bpy = 4,4'-联吡啶（1）、bpa = 1,2-双（4-吡啶基）乙烷（2）、bpe = 1,2-双（4-吡啶基）乙烯（3）和bpp = 1,2-双（4-吡啶基）丙烷（4））。对它们的固态结构进行了微调，以提高其在水溶液中的水解稳定性。尽管所有无溶剂MOFs中看似有足够的空隙空间，但只有热活化形式的MOF 2对CO表现出相对于N和H的选择性气体吸附能力。通过测定四种铜基金属有机框架材料1、2、3和4对五种细菌（包括大肠杆菌、金黄色葡萄球菌、肺炎克雷伯菌、铜绿假单胞菌和耐甲氧西林金黄色葡萄球菌，这些细菌在我们日常周围环境中很常见）的最低杀菌浓度（MBC）值，研究了它们的抗菌活性。尽管在抗菌活性测试中发现这些铜基金属有机框架材料在水性介质中结构非常稳定，但它们对所有五种细菌（包括革兰氏阳性菌（金黄色葡萄球菌和耐甲氧西林金黄色葡萄球菌）和革兰氏阴性菌（大肠杆菌、肺炎克雷伯菌和铜绿假单胞菌））均表现出优异的抗菌活性，且MBC值非常低。具有表面活性金属位点的坚固三维框架而非少量浸出的铜离子可能在使各种细菌失活方面发挥更强的作用，并降低主要由浸出金属离子引起的潜在细胞毒性。
