Armenian Journal of Physics=Ֆիզիկայի հայկական հանդես
National University of Architecture and Construction of Armenia, Yerevan
Simple and easily accessible spectrophotometric method for estimating the thermodynamic parameters of the ligands-nucleic acid interaction is suggested. The method has been used to determine the binding constant (K), Gibbs free energy (ΔG), enthalpy (ΔH) and entropy (ΔS) changes for mitoxantrone (MTX)-DNA and Ethidium bromide (EtBr)- poly(A)poly(U) complexes at different temperatures and at 10-2M Tris buffer containing 0.1 M NaCl. Estimated negative sing of ΔG for both intercalators MTX and EtBr interaction with A and B- forms of nucleic acids pointed to the driving the spontaneously going binding process. Negative values of ΔH=-9.7 kcal/mol for MTX-DNA and – 7.6 kcal/mol for EtBrpoly(A)⋅poly(U) were found, which indicated to the low energy levels of complexes. Positive entropy values of ΔS=5.2cal/(mol⋅K) for MTX-DNA and ΔS=3.8cal/(mol⋅K) for EtBrpoly(A)⋅poly(U) complexes reflected a structural changes due to the intercalation.To illustrate the general applicability of the suggested simple method the thermodynamic parameters of two intercalators interaction with nucleic acids have been determined which are consistent with the existing in literature binding data of well known ligand EtBr and MTX binding with nucleic acids.
oai:arar.sci.am:23474
ՀՀ ԳԱԱ Հիմնարար գիտական գրադարան
Dec 13, 2023
Feb 27, 2020
31
https://arar.sci.am/publication/26233
Edition name | Date |
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Simple Method for Determining the Thermodynamic Parameters of Ligand with Nucleic Acids Interaction | Dec 13, 2023 |