Retraction of “Two mixed-ligand coordination polymers based on 2,5-thiophenedicarboxylic acid and flexible N-donor ligands: The protective effect on periodontitis via reducing the release of IL-1β and TNF-α”

Two novel mixed-ligand coordination polymers, {[Co(tdc)(btrp)]·0.67DMF}n (1) and {[Zn2(bimb)2(tdc)2]·2H2O}n (2) involving 2,5-thiophenedicarboxylate (H2tdc), and bitopic flexible N-donor ligands, 1,3-bis(1,2,4-triazol-1-yl)propane (btrp) and 1,4-bis((1H-benzo[d]imidazol-1-yl)methyl)benzene (bimb), have been synthesized by the hydrothermal method and characterized via IR, elemental analysis, thermal analysis, and powder X-ray diffraction. The biological functional studies were performed; the treatment activity of the compounds on periodontitis and the specific mechanism was explored. First, the real-time RT-PCR was carried out to determine the inflammatory genes nf-κb and p53 relative expression in periodontal mucosal cells after treating with compounds 1 and 2. Then, the level of the inflammatory cytokine in the gingival crevicular fluid after treating with compounds was also determined by the ELISA detection kit.