Simultaneous/Selective Detection of Dopamine and Ascorbic Acid at Synthetic Zeolite-Modified/Graphite-Epoxy Composite Macro/Quasi-Microelectrodes

Sensors

Elida Cristina Ilinoiu²  Florica Manea²  Pier Andrea Serra¹ 

[1] Department of Clinical and Experimental Medicine, University of Sassari, Viale. San Pietro 43/b, Sassari 07100, Italy; E-Mail:;Department of Applied Chemistry and Engineering of Inorganic Compounds and Environment, Politehnica University of Timisoara, Victoriei Sqr., No. 2, Timisoara 300006, Romania; E-Mails:

关键词: dopamine;    ascorbic acid;    voltammetric detection;    amperometric detection;    synthetic zeolite-modified graphite-epoxy composite;    macroelectrode;    quasi-microelectrode;   

DOI  :  10.3390/s130607296

来源: mdpi

【 摘 要 】

The present paper aims to miniaturize a graphite-epoxy and synthetic zeolite-modified graphite-epoxy composite macroelectrode as a quasi-microelectrode aiming in vitro and also, envisaging in vivo simultaneous electrochemical detection of dopamine (DA) and ascorbic acid (AA) neurotransmitters, or DA detection in the presence of AA. The electrochemical behavior and the response of the designed materials to the presence of dopamine and ascorbic acid without any protective membranes were studied by cyclic voltammetry and constant-potential amperometry techniques. The catalytic effect towards dopamine detection was proved for the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode, allowing increasing the sensitivity and selectivity for this analyte detection, besides a possible electrostatic attraction between dopamine cation and the negative surface of the synthetic zeolite and electrostatic repulsion with ascorbic acid anion. Also, the synthetic zeolite-modified graphite-epoxy composite quasi-microelectrode gave the best electroanalytical parameters for dopamine detection using constant-potential amperometry, the most useful technique for practical applications.

【 授权许可】

CC BY   
© 2013 by the authors; licensee MDPI, Basel, Switzerland.