RETRACTED: Two mixed-ligand coordination polymers: Magnetic properties and biological evaluation on myofascial pain syndrome by reducing IL-6 release (Retracted article. See vol. 320, 2023)

Two coordination polymers (CPs) based on Co(II) and Cu(II) ions as metal centers were produced via alternation of auxiliary polycarboxylates with solvothermal reactions between corresponding metal salts and 3,3',5,5'-tetra(1H-imidazole-1-yl)-1,1'-biphenyl (L), and their chemical formulae are [Cu-2(L)(2,6-NDC)(OAc)(2)]center dot 2H(2)O (1) and [Co-2(L)(BPnDC)(2)]center dot 6H(2)O (2) (H(2)BPnDC = 4,4'-carbonyldibenzoic acid and 2,6-H2NDC = 2,6-naphthalic acid). The two compounds' magnetic performances suggested antiferromagnetic coupling interactions between the adjacent metal ions. Their protective activity on myofascial pain syndrome was assessed, and their specific mechanism was studied simultaneously. First, enzyme-linked immunosorbent assay detection was carried out to assess the inflammatory cytokine TNF-alpha and IL-6 levels released from fascial cells. Then, the activation of inflammatory response in fascial cells was measured through real-time reverse transcription-polymerase chain reaction by evaluating the p53 and nf-kappa b relative expression levels after treatment with the compound. A hemolysis test was conducted to evaluate the safety of the new compounds, and CCK-8 assay was finished to explore the cytotoxicity of compounds 1 and 2.