ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Synthesis and characterisation of a novel bi-nuclear copper²⁺ complex and its application as electrode-modifying agent for simultaneous voltammetric determination of dopamine and ascorbic acid

Diganta Kumar Das, Babita Sarma, and Sangita Haloi

Department of Chemistry, Gauhati University, 781 014, Guwahati, Assam, India

E-mail: digantakdas@gmail.com

Abstract: A new binuclear complex of copper²⁺, [LCu²⁺(CH₃COO)₂Cu²⁺L](CH₃COO)₂ where L is N,N-bis(phthalimide)ethylenediamine, was synthesised and characterised. The complex ion [LCu²⁺ (CH₃COO)₂Cu²⁺L]²⁺ was encapsulated into ZSM-5 zeolite and used to modify the surface of the glassy carbon electrode. This modified electrode, in a phosphate buffer solution at pH 7.0, exhibited an oxidation potential for dopamine (DA) and ascorbic acid (AA) at electrode potentials of 0.230 V and −0.090 V vs. Ag/AgCl respectively, a separation of 0.320 V. The electro-oxidation of DA or AA on the modified electrode is independent of each other. No interference was observed from Na⁺, K⁺, Cl⁻, SO ₄ ²⁻ , Mg²⁺, Ca²⁺, Zn²⁺, Fe²⁺, and glucose. The detection limits obtained were 2.91 × 10⁻⁷ M for DA and 3.5 × 10⁻⁷ M for AA.

Keywords: ascorbic acid – dopamine – ZSM-5 zeolite – voltammetry – sensor

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-013-0431-8

Chemical Papers 68 (2) 153–163 (2014)