International Journal of Nanomedicine (Aug 2023)
Green Synthesis of MOF-Mediated pH-Sensitive Nanomaterial AgNPs@ZIF-8 and Its Application in Improving the Antibacterial Performance of AgNPs
Abstract
Zhiqiang He,1 Huan Yang,1 Yufan Gu,1 Yuhan Xie,1 Jianan Wu,1 Chen Wu,1 Jiawei Song,1 Maofang Zhao,2,3 Da Zong,1 Wenlong Du,1 Jiaju Qiao,1 Yipeng Pang,1– 3 Yi Liu1– 3 1Department of Biophysics, School of Life Sciences, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, People’s Republic of China; 2School of Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, People’s Republic of China; 3Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, People’s Republic of ChinaCorrespondence: Yi Liu; Yipeng Pang, Department of Biophysics, School of Life Sciences, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, People’s Republic of China, Tel/Fax +86-0516-83262084, Email [email protected]; [email protected]: Herein, an emerging drug delivery system was constructed based on zeolite imidazole backbone (ZIF-8) to improve antibacterial defects of nanosilver (AgNPs), such as easily precipitated and highly cytotoxic.Methods: The homogeneous dispersion of AgNPs on ZIF-8 was confirmed by UV-Vis spectroscopy, FTIR spectroscopy, particle size analysis, zeta potential analysis, and SEM. The appropriate AgNPs loading ratio on ZIF-8 was screened through the cell and antibacterial experiments based on biosafety and antibacterial performance. The optimal environment for AgNPs@ZIF-8 to exert antibacterial performance was probed in the context of bacterial communities under different acid-base conditions. The potential mechanism of AgNPs@ZIF-8 to inhibit the common clinical strains was investigated by observing the biofilm metabolic activity and the level of reactive oxygen species (ROS) in bacteria.Results: The successful piggybacking of AgNPs by ZIF-8 was confirmed using UV-Vis spectroscopy, FTIR spectroscopy, particle size analysis, zeta potential analysis, and SEM characterization methods. Based on the bacterial growth curve (0– 24 hours), the antibacterial ability of AgNPs@ZIF-8 was found to be superior to AgNPs. When the mass ratio of ZIF-8 and AgNPs was 1:0.25, the selection of AgNPs@ZIF-8 was based on its superior antimicrobial efficacy and enhanced biocompatibility. Notably, under weakly acidic bacterial microenvironments (pH=6.4), AgNPs@ZIF-8 demonstrated a more satisfactory antibacterial effect. In addition, experiments on biofilms showed that concentrations of AgNPs@ZIF-8 exceeding 1×MIC resulted in more than 50% biofilm removal. The nanomedicine was found to increase ROS levels upon detecting the ROS concentration in bacteria.Conclusion: Novel nanocomposites consisting of low cytotoxicity drug carrier ZIF-8 loaded with AgNPs exhibited enhanced antimicrobial effects compared to AgNPs alone. The pH-responsive nano drug delivery system, AgNPs@ZIF-8, exhibited superior antimicrobial activity in a mildly acidic environment. Moreover, AgNPs@ZIF-8 effectively eradicated pathogenic bacterial biofilms and elevated the intracellular level of ROS.Graphical Abstract: Keywords: MOF, ZIF-8, AgNPs, nanocomplex, ROS, pathogenic biofilm