Experimental and theoretical studies of interaction of aliphatic chain α-aminobisphosphonates with DNA

Abstract

Abstract The interaction of DNA with four aliphatic chain α-aminobisphosphonate were investigated in a tris–hydrogen chloride buffer (pH 7.4) in the presence and absence of spectroscopic probes (Neutral Red dye (NR) and Hoechest (Ho)) by fluorescence, UV–Vis absorption and circular dichroism (CD) spectroscopic methods, electrochemical techniques and viscometry. The spectroscopic and voltammetric studies showed that the groove binding mode of interaction is predominant in the solution containing DNA and α-aminobisphosphonates. Furthermore, the results indicated that the binding strength of the DNA–α-aminobisphosphonate complexes are dependent on alkyl moiety presented in the structure of α-aminoalkylphosphonic acids A1–A4. The principal component analysis (PCA) and theoretical quantum mechanical and molecular mechanics (QM-DFT/B3LYP/6-31+G* and MM-SYBYL) methods were also applied to determine the number of chemical components presented in complexation equilibrium and identify the structure complexes of DNA with α-aminobisphosphonates, respectively.