Comparison of carboplatin and cisplatin effects on DNA structure in solution

Abstract

The formation of complexes of high molecular thymus DNA with coordination compounds of platinum( II) cisplatin and carboplatin has been examined. The absorption spectra, circular dichroism spectra, DNA melting and change in reduced viscosity of DNA solutions containing different concentrations of platinum compounds have been analyzed. It was shown that DNA interacts with cisplatin and carboplatin in a solution containing 0.005M NaCl. The nitrogenous bases of macromolecules participate in binding. Spectral changes of DNA and the dependence of the reduced viscosity of DNA solutions on the concentration of platinum compounds show similar features in complex formation when using cisplatin and carboplatin, but at the same time they also indicate differences in the influence of cisplatin and carboplatin on DNA structure. Apparently, unlike the interchain cross-linking formed by cisplatin, carboplatin binds to a single DNA strand.