Electrochemical detection of dopamine on a Ni/Al layered double hydroxide modified carbon ionic liquid electrode

Abstract

In this paper a Ni/Al layered double hydroxide (LDH) was first synthesized and further immobilized on a carbon ionic liquid electrode (CILE), which was prepared by using 1-(3-chlorine-2-hydroxypropyl)-3-methylimidazolium acetate as the modifier. The characteristics of LDH/CILE were investigated by scanning electron microscopy (SEM) and cyclic voltammetry. Under the selected conditions the LDH/CILE showed better electrochemical response towards the detection of dopamine (DA) than the CILE. The parameters of DA electro-oxidation on the LDH/CILE were calculated with the values of the electron transfer coefficient ( α), the number of electrons transferred ( n), the apparent heterogeneous electron transfer rate constant ( k s) and the diffusion coefficient ( D) as 0.426, 2.25, 1.66 s −1 and 7.06 × 10 −5 cm 2/s, respectively. This modified electrode can be further used to detect DA content in the real drug samples.