Preparation of spherical metal-organic frameworks encapsulating ag nanoparticles and study on its antibacterial activity

A metal-organic frameworks (CuTCPP MOFs) were synthesized with Cu(NO3)2·3H2O and 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin (TCPP) by the solvothermal method. The structure and morphology of the CuTCPP MOFs were characterized by UV-vis absorption spectra, X-ray diffraction (PXRD), energy dispersive spectra, scanning electron microscopy (EDS-SEM) and transmission electron microscopy (TEM). The structure of the as-synthesized MOF includes copper ions and copper metalloporphyrin (Cu-TCPP) by UV-vis absorption spectra and PXRD. The SEM and TEM images of the as-synthesized MOF showed the morphology of the CuTCPP MOFs were spherical. The as-synthesized spherical MOFs as the carriers were used to encapsulate the Ag nanoparticles and prepared Ag-CuTCPP MOFs. The Ag-CuTCPP MOFs was also characterized by UV-vis, PXRD, SEM and TEM. The Ag nanoparticles were completely encapsulated into the CuTCPP MOFs and no surface absorption, which have been confirmed by comparing TEM and SEM-EDS of Ag-CuTCPP MOFs before crushing with that of Ag-CuTCPP MOFs after crushing. In addition, the release of Ag ions from Ag-CuTCPP MOFs was also investigated by Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES). Furthermore, the antimicrobial activities and cytotoxicity of Ag-CuTCPP MOFs were performed by in vitro and in vivo experiment. In vitro, the antibacterial effect of Ag-CuTCPP MOFs was even better than that of the penicillin as the positive control and the cytotoxicity of Ag-CuTCPP MOFs was significantly lower than that of naked Ag nanoparticles and Ag ions; in vivo, Ag-CuTCPP MOFs not only exhibited the excellently antibacterial effect and extremely low cytotoxicity but also effectively promoted the wound healing.