Experimental and theoretical studies of electrochemical characteristics of 3,4-dihydroxyphenylacetic acid (DOPAC)

被引:24
作者
Zare, Hamid R. [1 ]
Namazian, Mansoor [1 ,2 ]
Coote, Michelle L. [2 ]
机构
[1] Yazd Univ, Dept Chem, Yazd, Iran
[2] Australian Natl Univ, ARC Ctr Excellence Free Rad Chem & Biotechnol, Res Sch Chem, Canberra, ACT 0200, Australia
基金
澳大利亚研究理事会;
关键词
DOPAC; Electrochemical behavior; Standard redox potentials; G3; Ab initio calculations; GLASSY-CARBON ELECTRODE; ADENINE-DINUCLEOTIDE NADH; SELF-ASSEMBLED MONOLAYERS; ELECTROCATALYTIC OXIDATION; GOLD ELECTRODE; FREE-ENERGIES; METABOLITE; MOLECULES; HYBRID; PROTON;
D O I
10.1016/j.electacta.2009.04.012
中图分类号
O646 [电化学、电解、磁化学];
学科分类号
081704 ;
摘要
The electrochemical behavior of 3,4-dihydroxyphenylacetic acid (DOPAC) in aqueous solutions with different pHs and DOPAC concentrations was studied by cyclic voltammetry at various potential scan rates. The electro-oxidation of DOPAC involves a transfer of two electrons and two protons in solutions of pH < 8.0 and a transfer of two electrons and one proton in Solutions of pH > 8.0, in agreement with the one-step two-electron mechanism. The cyclic voltammetry indicated that the process of electro-oxidation of DOPAC follows an E(r)C(i) mechanism. The standard redox potential, E(0)', two-proton-two-electron and one-proton-two-electron processes of DOPAC were determined as 0.585 and 0.357 V versus saturated calomel electrode (SCE), respectively. The acidic dissociation constant of DOPAC was also obtained. Also, the diffusion coefficient of DOPAC was calculated as 9.2 x 10(-6) cm(2) s(-1) for the experimental conditions, using chronoamperometric results. The standard reduction potentials and the second acidic constant of DOPAC have been also calculated using standard ab initio calculations at the G3 level of theory in conjunction with a continuum solvation model. The theoretical values are in good agreement with experiment (C) 2009 Elsevier Ltd. All rights reserved.
引用
收藏
页码:5353 / 5357
页数:5
相关论文
共 28 条
[1]  
[Anonymous], 2016, GAUSSIAN 16 REV B01
[2]  
Bard A. J., 1985, STANDARD POTENTIALS
[3]  
Bard A.J., 2001, ELECTROCHEMICAL METH
[4]   Quantum calculation of molecular energies and energy gradients in solution by a conductor solvent model [J].
Barone, V ;
Cossi, M .
JOURNAL OF PHYSICAL CHEMISTRY A, 1998, 102 (11) :1995-2001
[5]   THERMODYNAMICS OF THE ELECTRON AND THE PROTON [J].
BARTMESS, JE .
JOURNAL OF PHYSICAL CHEMISTRY, 1994, 98 (25) :6420-6424
[6]   Gaussian-3 (G3) theory for molecules containing first and second-row atoms [J].
Curtiss, LA ;
Raghavachari, K ;
Redfern, PC ;
Rassolov, V ;
Pople, JA .
JOURNAL OF CHEMICAL PHYSICS, 1998, 109 (18) :7764-7776
[7]  
Frisch A., 2003, Gaussian 03 User's Reference
[8]  
Hehre M. J., 1986, Ab initio Molecular Orbital Theory
[9]   Mechanistic study of the oxidation of caffeic acid by digital simulation of cyclic voltammograms [J].
Hotta, H ;
Ueda, M ;
Nagano, S ;
Tsujino, Y ;
Koyama, J ;
Osakai, T .
ANALYTICAL BIOCHEMISTRY, 2002, 303 (01) :66-72
[10]   COSMO - A NEW APPROACH TO DIELECTRIC SCREENING IN SOLVENTS WITH EXPLICIT EXPRESSIONS FOR THE SCREENING ENERGY AND ITS GRADIENT [J].
KLAMT, A ;
SCHUURMANN, G .
JOURNAL OF THE CHEMICAL SOCIETY-PERKIN TRANSACTIONS 2, 1993, (05) :799-805