A Prussian Blue/Cobalt Oxide/Carbon Nanotube Composite for Homovanillic Acid Detection

Abstract

ABSTRACT

Homovanillic acid is a metabolite produced by dopamine which is a neurotransmitter in the human body. Raised homovanillic acid levels may be indicator of neurological diseases such as schizophrenia, Parkinson’s disease. To study the levels of homovanillic acid, Prussian Blue and Co3O4 particles were tethered to COOH-MWNT to produce a composite used to modify the surface of glassy carbon electrode. The resulting modified glassy carbon electrode is able to detect homovanillic acid concentrations between 1 µM to 70 µM. The technique employed is the cyclic voltammetry technique, this technique measures relationship between current and potential in the electrochemical responses of the homovanillic acid solutions to the composite electrode. To ensure optimum detection, pH, and loading volume of composite were varied. The modified glassy carbon electrode showed selectivity against interferent such as ascorbic acid and uric acid. Characterization of the composite used to modify the glassy carbon electrode was done by energy dispersive X-Ray analysis and transmission electron microscopy respectively.