Electrochemical and theoretical evaluation of the interaction between dna and amodiaquine: evidence of the guanine adduct formation

Abstract

Recebido em 4/9/09; aceito em 3/2/10; publicado na web em 18/6/10The electrochemical behavior of the interaction of amodiaquine with DNA on a carbon paste electrode was studied using voltametric techniques. In an acid medium, an electroactive adduct is formed when amodiaquine interacts with DNA. The anodic peak is dependent on pH, scan rate and the concentration of the pharmaceutical. Adduct formation is irreversible in nature, and preferentially occurs by interaction of the amodiaquine with the guanine group. Theoretical calculations for optimization of geometry, and DFT analyses and on the electrostatic potential map (EPM), were used in the investigation of adduct formation between amodiaquine and DNA.

Research progress in electroanalytical techniques for determination of antimalarial drugs in pharmaceutical and biological samples

“…The cyclic voltammetric behaviour of AQ was investigated at a bare and DNA modied CPE in BR buffer (pH 4.0) studying the dynamics of DNA mediation in the transfer of electrons. 80 Well-dened anodic and cathodic peaks were obtained at both the electrodes. Though there was not much variation in peak potential, a remarkable improvement in peak current was observed at DNA modied CPE.…”

“…80 Welldefined anodic and cathodic peaks were obtained at both the electrodes. 80 Welldefined anodic and cathodic peaks were obtained at both the electrodes.…”

“…100,106 Enzymes are also used as labels attached to antigens, antibodies and oligonucleotides with a specific sequence providing affinity-based sensors. 46,61,80,118 polypyrrole modified electrodes were formed on PGE and successfully used to determine the drug. 134 The drug was quantified by competitive binding between DC and a HRP-labeled specific tracer for binding sites of the captured antibodies immobilized on the surface of protein-functionalized magnetic beads.…”

“…DNA strands have been used as receptors for antimalarial drug detection since they possess rich functional active groups such as amino groups and carbonyl groups, and could bind with drug molecules through electrostatic interactions, hydrogen bond and hydrophobic interactions. 46,61,80,118 Peptides are amino-acids sequences which hold possibility of being used as a receptor for antimalarial drug detection since it may, like DNA, form tertiary structures where the drug cations can bind. Similar to DNA, peptides can be synthesized and selected by automated routes in a combinatorial way, and hence, hold promise to function as effective recognition elements in electrochemical sensors for analysis of antimalarial drugs.…”

Insights into the Binding Mechanism of Ascorbic Acid and Violaxanthin with Violaxanthin De-Epoxidase (VDE) and Chlorophycean Violaxanthin De-Epoxidase (CVDE) Enzymes: Docking, Molecular Dynamics, and Free Energy Analysis

“…The Density functional theory (DFT) is presently the most successful approach to compute the electronic-structure properties [Patel et al, 2004]. Popular quantum mechanical descriptors such as the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) play a major role in governing many chemical reactions [Arguelho et al, 2010;Singh et al, 2011]. Electronic descriptors that correlate to the physicochemical properties of molecules are energies of FMOs, band gap, total energy, dipole moment, ionization potential (IP), electron affinity (EA), electro negativity (χ), chemical potential (μ), global chemical hardness (η), global chemical softness (σ), electrophilicity index (ω), nucleophilicity (N), and hydrogen bond strength.…”