Antibacterial and DNA interaction studies of zinc(II) complexes with quinolone family member, ciprofloxacin

DNA binding and cleavage characteristics of Zn(II) complexes have been investigated. The DNA interaction property of the complexes has been investigated using absorption spectra, viscosity measurements, as well as gel electrophoresis studies. Intrinsic binding constant (K-b) has been estimated under similar set of experimental conditions. Absorption spectral study indicate that the Zn(II) complexes intercalate between the base pairs of the DNA tightly with intrinsic binding constant in the range of 1.0 x 10(4)-4.0 x 10(4) M-1 in phosphate buffer. The proposed DNA binding mode supports the large enhancement in the relative viscosity of DNA on binding. The antimicrobial activity of all the ligands and metal complexes has been examined by minimum inhibitory concentration method (MIC). (C) 2009 Elsevier Masson SAS. All rights reserved.