Albany 2015:Book of Abstracts
June 9-13 2015
©Adenine Press (2012)
Interaction of Doxorubicin with Tumor DNA, Irradiated by Electromagnetic Millimetric Non-thermal Waves
The interaction of anticancer drug doxorubicin with sarcoma-45 DNA (tDNA) was studied using spectrophotometric method. Nucleic acid was extracted from the sarcoma-45 tumour cells and it was irradiated by non-thermal with resonant (64.5 and 50.3 GHz) frequencies of water structures for 60 minutes. Recently, it has been revealed that as a result of tDNA irradiation with non-thermal coherent electromagnetic waves the shape of melting curve changes slightly and the melting temperature increases approximately by 1.5°C, when melting interval is almost constant (Kalantaryan et al., 2014).
Absorption curves at visible spectra have been obtained for the non-irradiated and irradiated tDNA complexes with doxorubicin. From the absorption spectra, binding isotherms in Scatchard coordinates were built and the values of binding constants have at 290, 310 and 310K temperatures have been determined. At the mentioned temperatures tDNA is in double-stranded helical form (Kalantaryan et al., 2014). Using approaches given in (Marky et al., 1983) the changes of enthalpy (ΔH) and entropy (ΔS) due to the complex-formation of doxorubicin with tDNA have been determined.
Calculations show, that ΔH for irradiated tDNA complexes with doxorubicin is greater in absolute value (-4.3kcal/mol) from the corresponding value of non-irradiated tDNA complexes with doxorubicin (-2.8kcal/mol). However, ΔS increase relatively less. In case of non-irradiated tDNA ΔS=16.6 kcal/mol.K, while in case of irradiated tDNA ΔS=18.5 kcal/mo.K. Consequently, the changes in thermodynamic parameters for tDNA-doxorubicin complex-formation, when nucleic acid is irradiated by 64.5 and 50.3 GHz frequencies is greater, than in case of non-irradiated tDNA.
L.A. Marky, J.G. Snydee, D.P. Remeta, K.J. Breslauer. (1983). Thermodynamics of drug-DNA interactions. J. Biomol Struct. Dyn. 1, 487-507.
1Sergey H. Hakobyan
2Department of Machine Science