Electrochemical Construction of a Polymer-Metal Complex Surface Network for Selective Determination of Dopamine in Blood Serum

Abstract

A surface base polymeric film was fabricated onto a glassy carbon electrode (GCE) via reversible voltammetric scanning in acidic electrolyte containing a (2,4,6-triaminopyrmidine) monomer (TP). The assembled poly(2,4,6-triaminopyrmidine) (PTP) surface material was further modified by electrochemical attachment of tris(2,2'-bipyridine) ruthenium(II) described as Ru(II)-complex. The structure and electrochemical properties of the resulting (Ru-PTP-GCE) surface network were characterized using X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The apparent estimated value of electron transfer rate constant (k_app) of the prepared sensor was three times greater than the virgin PTP. The cooperative effects of the (PTP) and Ru(II)-complex composite increased the efficiency and the stability of the proposed sensor for the selective determination of dopamine (DA) in the presence of ascorbic acid (AA) and uric acid (UA). The detection limit (DL3σ) of DA in this environment was 0.021 μM. The fabricated sensor was successfully applied for DA detection in a blood serum sample with satisfactory recovery.

Keywords:

• ascorbic acid
• dopamine
• poly(2,4,6-triaminopyrimidine)
• ruthenium(II) complex

Disclosure statement

The authors declare that they have no known competing financial interests or personal relationships that influenced the work reported in this paper.

Additional information

Funding

The authors would like to thank Sultan Qaboos University (SQU), Sultanate of Oman, for supporting this work by grant number (IG/SCI/CHEM/18/01).