Electrochemical Behaviours and Detection of Adenosine-5′-triphosphate on an Ionic Liquid Modified Carbon Paste Electrode

In this paper a new electrochemical method based on the ionic liquid modified carbon paste electrode (IL-CPE) was proposed for the determination of adenosine-5'-triphosphate (ATP) in a pH 4.5 Britton-Robinson (B-R) buffer solution. IL-CPE was prepared by using 1-butyl-3-methylimidazolium trifluoroacetate (BMIMCF3COO) as the modifier. Cyclic voltammetry was used to investigate the electrochemical behaviors of ATP on the IL-CPE, and the results indicated that IL-CPE exhibited strong electrocatalytic ability to promote the oxidation of ATP with a single well-defined irreversible adsorption-controlled oxidation peak appeared. The electrochemical reaction parameters of ATP were calculated with the results of the electron transfer coefficient (alpha) as 0.40, the electron transfer number (n) as 1.17, the apparent heterogeneous electron transfer rate constant (ks) as 3.66 x 10(-6) s(-1) the surface coverage (Gamma(T)) as 2.48 x 10(-9) mol cm(-2). Under the selected conditions the proposed IL-CPE showed good performances to the ATP detection in the concentration range from 0.1 to 1000.0 mu mol L-1 with the detection limit as 3.65 x 10(-8) mol L-1 (3 sigma) by differential pulse voltammetry. The method showed good selectivity to the ATP detection without the interferences of coexisting substances and was successfully applied to the ATP injection samples detection with satisfactory results.