Microporous MOF with open metal sites for CO2 fixation and protective effect on osteoarthritis by regulating the activation of PI3K/AKT pathway

Abstract A novel microporous metal-organic framework (MOF) based on Zn(II) ion as node with the chemical formula of {[Zn(H2O)(HL)]·(DMF)2(H2O)2}n (1, H3L = 2-(4-carboxyphenyl)-1H-benzo[d]imidazole-5-carboxylic acid, DMF = N,N-dimethylformamide), which has rich water-coordinated metal centers and high density of free N-donor groups has been successfully prepared via H3L ligand and Zn(NO3)2·6H2O reaction within H2O, EtOH along with DMF mixed solvent. The presence of open metal sites along with the basic N-donor sites in the resulting activated 1a induces a moderate high sorption capacity of CO2. In addition, because of basic N-donor groups along with Lewis acidic Zn2+ ions, 1a has become an efficient heterogeneous catalyst, which can chemically fix CO2 in the carbonate of cyclic annular at mild room temperature. Furthermore, the influence of compound on the activation of PI3K/AKT signaling pathway was studied by Western blot. The ELISA was carried out the evaluate the IL-18 and IL-6 content in synovial cells after compound treatment.