Cobalt(II) and zinc(II) complexes with 2-propionate-based non-steroidal anti-inflammatory drugs.

Three cobalt(II) and three zinc(II) complexes with the non-steroidal anti-inflammatory drugs fenoprofen, loxoprofen and flurbiprofen as ligands were synthesized and characterized with diverse techniques including single-crystal X-ray crystallography. The in vitro scavenging activity of the complexes against 1,1-diphenyl-picrylhydrazyl and 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) free radicals and the ability to reduce H2O2 were studied in the context of the antioxidant activity studies. The complexes have shown significant activity towards H2O2. Antimicrobial testing against four bacteria revealed that the complexes were more active than free drugs. The complexes may interact with calf-thymus DNA via intercalation as revealed from the techniques employed. The affinity of the complexes for bovine and human serum albumins was evaluated by fluorescence emission spectroscopy and the corresponding binding constants revealed reversible binding to both albumins.