Electrochemical methods for determination of thymine in medical pipefish samples based on HPMaFP/Ppy/GCE-modified electrode

摘要

A sensitive electrochemical method was developed for the voltammetric determination of thymine at a composite film-modified electrode 1-phenyl-3-methyl-4-(2-furoyl)-5-pyrazolone (HPMαFP)/polypyrrole (Ppy)/glassy carbon electrode (GCE). The electrochemical parameters of thymine were investigated by cyclic voltammetry and differential pulse voltammetry. In pH=7.4, one sensitive oxidation peak of thymine with E_(pa)=0.968 V was observed on the HPMαFP/PPy-modified electrode. The difference of peak potential (ΔE_(pa)) was 188 mV lower than that for bare GCE. Compared to the bare GCE and Ppy/GCE, the HPMaFP/Ppy/GCE-modified electrode showed an excellent electrocatalytic effect on the oxidation of thymine and displayed a shift of the oxidation potential in the negative direction with significant increase in the peak current. Under the optimum condition, the concentration calibration range and detection limit are 2x10~(-6)-1 x 10~(-4) and 4.85 x 10~(-7)M for thymine. This developed method had been apphed to the direct determination of thymine in medical pipefish samples with satisfactory results.