Electrochemical Study of Doxorubicin Interaction with Different Sequences of Double Stranded Oligonucleotides, Part II.
Department of Paediatric Haematology and Oncology
Abstract
PART 1
Doxorubicin is a known anticancer drug intercalating into dsDNA. The mechanism of interaction of doxorubicin with ssDNA is not clear. In this study, adsorptive transfer stripping technique coupled with square wave voltammetry was used for studying of interaction of doxorubicin with single stranded oligonucleotides (ssODN) in various ratios (1:1, 1:2 and 1:5) and interaction times (0–300 min.). When comparing the results for three ratios of the mixture between drug and ssODN we found that the interval of peak intensities of oligonucleotide reduced with the increasing ratio of oligonucleotide-doxorubicin, i.e. for ratio 1:1 it is 25–85 %, for ratio 1:2 it is 16–60 % and for ratio 1:5 it is 19–51 %. The interval of relative signal intensities of doxorubicin ranges from 8 to 100 % for ratio 1:1, 22–100 % for ratios 1:2 and 1:5. The results showed the assumption that DOXO peak height increased with increasing concentration of the drug intercalated into ssODN, but the signals CA peaks changes during the interaction suggest the changes in the structure of ssODN.
PART 2
Interaction of low molecular weight compounds with DNA is one of general mechanisms utilized for an effective anticancer therapy. The anthracycline doxorubicin is one of the drugs that represent the compound with such effect. In our previous work [Hynek et al., Int. J. Electrochem, Sci. 7 (2012) xx] the electrochemical behaviour of doxorubicin interaction with single stranded ODN by using adsorptive transfer stripping square wave voltammetry was described. This paper is focused on the study of interaction of doxorubicin with double stranded ODNs (dsODNs) using the same technique. Here, we used four dsODNs possessing different primary structuresand observed the changes in their electrochemical behaviour after their treatment with three concentrations of doxorubicin for 5 hours. The changes found are discussed and differences in behaviours of individual dsODNs described and associated with their structure.
