Kou YY, Li ML, Ren XH. Synthesis, structure, and DNA binding/cleavage of two novel binuclear Co(II) complexes.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2018;
205:435-441. [PMID:
30055453 DOI:
10.1016/j.saa.2018.07.050]
[Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 07/16/2018] [Accepted: 07/17/2018] [Indexed: 06/08/2023]
Abstract
In this study, two novel binuclear Co(II) complexes, [Co4(L1)2(CH3CH2O)4·5.5H2O (1) and [Co2(L2)2(CH3COO)(H2O)]·2CH3OH·3H2O (2)], with the ligands H3L1 and H2L2 were synthesized and structurally characterized using single crystal X-ray diffraction. The crystal structures of complex 1 and 2 belong to a monoclinic system with space group of P2(1)/n and triclinic system with space group of P-1, respectively. Their interaction with CT-DNA was investigated using electron absorption and fluorescent spectroscopy. The apparent binding constants (Kapp) of two complexes (1 and 2) were determined to be 5.34 × 105 and 5.82 × 105, respectively, and both exhibited a moderate intensity of insertion with 2 > 1. Fluorescence quenching studies indicated that the fluorescence quenching mechanism of complex 1 is dynamic quenching and that of complex 2 is a static quenching mechanism. The chemical nuclease activity of the complexes was studied using agarose gel electrophoresis. The results suggest that when H2O2 is added, complexes 1 and 2 exhibit chemical nuclease activity. The cleavage mechanisms between the complexes and plasmid DNA are the likely oxidative cleavage process of hydroxyl radical (OH) and singlet oxygen (1O2) as active species.
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