DNA cleavage, binding and intercalation studies of drug-based oxovanadium(IV) complexes

Abstract

The complexes of oxovanadium(IV) with ciprofloxacin and various uni-negative bidentate ligands have been prepared and their structure investigated using spectral, physicochemical and elemental analyses. The viscosity measurement suggest that the complexes bind to DNA by intercalation. The DNA binding efficacy was determined using absorption titration to obtain the binding constant (K_b). The DNA cleavage efficacy was determined using gel electrophoresis. The DNA binding and cleavage efficacy were increased in the complexes relative to the parental ligands and metal salts. Antibacterial activity has been assayed against two Gram^{( − ve)} i.e. Escherichia coli, Pseudomonas aeruginosa and three Gram^{( + ve)} Staphylococcus aureus, Bacillus subtilis, Serratia marcescens microorganisms using the doubling dilution technique. The results show a significant increase in antibacterial activity in the complexes compared with parental ligands and metal salts.

Keywords::

• Drug based oxovanadium(IV) complexes
• MIC
• intrinsic binding constants (K_b)
• gel electrophoresis and viscometric techniques
• antimicrobials

Acknowledgements

We wish to express our gratitude to Prof. J. S. Parmar, Head, Department of Chemistry and Head, B & R Doshi School of Biosciences, Sardar Patel University, Vallabh Vidyanagar, Gujarat, India, for providing the necessary laboratory facilities. The authors are highly thankful to the UGC for financial assistance of UGC grant 32-226/2006(SR).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.