Water-Stable Silver-Based Metal-Organic Frameworks of Quaternized Carboxylates and Their Antimicrobial Activity.

Three-dimensional (3D) and two-dimensional (2D) Ag-based zwitterionic metal-organic frameworks (MOFs) [Ag(Cedcp)] (, 3D, HCedcpBr denotes -(carboxyethyl)-(3,5-dicarboxyl)-pyridinium bromide) and {[Ag(Cmdcp)(HO)]·4HO} (, 2D, HCmdcpBr denotes -(carboxymethyl)-(3,5-dicarboxyl)-pyridinium bromide) have been prepared and investigated for antimicrobial activity via minimal inhibition concentration (MIC) test and killing kinetic assay. Both MOFs and show good water stability and solubility ascribed to their characteristic aromatic rings and positively charged pyridinium of the ligands, as well as the presence of Ag on their surface, leading to strong antimicrobial activity and a wide antimicrobial spectrum toward Gram-negative and positive bacteria. The results indicated that MOF possesses a faster antibacterial activity (60 min) than MOF (120 min). Scanning electron microscopy analysis further suggests that the Ag-based MOFs are capable of rupturing the bacterial membrane, leading to cell death. Moreover, both MOFs exhibit little hemolytic activity against mouse erythrocytes and show good biocompatibility , rendering MOFs and potential therapeutic agents for diseases caused by bacteria.