New Silver(I) Lawsone-based complexes: Synthesis, characterization, interaction with biological macromolecules, in vitro antineoplastic, antimetastatic, and antimicrobial activity

Abstract

New silver(I) complexes of formula [Ag(Lw)]2 (1), [Ag(Lw)(B)], where (Lw= lawsonate, B = 2,2`bipyridine (bpy) (2), 1,10-phenanthroline (phen) (3) and [Ag(Lw)(PPh3)2], (PPh3=triphenylphosphine (4)) have been isolated and characterized using elemental analysis (C, H, N), and FTIR, NMR(1H, 13C and 31P), UV–visible spectroscopy along with thermal analysis and molar conductivity measurements. The resulting data showed that the lawsone coordinates to the Ag(I) as a mono-negative O,O-donor ligand. The interaction of the ligand and complexes with (ctDNA, calf thymus DNA, tRNA, yeast RNA, and BSA, bovine serum albumin) has been studied utilizing absorption and fluorescence spectroscopy. The binding constant data (Kb) revealed that the complexes interact with the biomolecules more strongly than the ligand (HLw). Furthermore, in vitro, cytotoxic activity against normal lung cells (WI38), and various malignant cells, including breast (MCF7 and MDA-231), and colon (HCT116) was studied using cisplatin as a standard drug. The IC50 and selective index (SI) data showed that complex (3) is more selective towards the HCT116 cells. Flow cytometric study of complex (3) revealed that cells are arrested in the G0/G1 phase and induced cell death by an apoptotic mechanism rather than necrosis. The anti-metastatic activity (wound healing) of complex (3) indicated its ability to prevent the migration of cancer cells. The antimicrobial activity of the compounds has been also studied against gram +ve, gram -ve bacteria, and yeast (C. Albican), using penicillin and miconazole, respectively as a reference to show that the complexes (1) and (3) possess the highest activity against these microorganisms.