Cysteamine (CA) is a high performance drug with a radiation protection effect on guanine (GA) and adenine
(AD). Therefore, we focus on the preparation of a highly sensitive electrochemical sensor for determination
of CA in the presence of GA and AD in biological samples. For this goal, a carbon paste electrode modified
with magnesium oxide nanoparticles (MgO/NPs) and N-(4-hydroxyphenyl)-3,5-dinitrobenzamide (N-4-
HP-DNBA) was fabricated. The efficiency of the proposed sensor was investigated for the
electrocatalytic oxidation of CA in the presence of GA and AD for the first time. The mediated oxidation
of CA at the N-4-HP-DNBA/MgO/NPs/CPE was investigated using an electrochemical approach. The
electro-oxidation peak currents for CA, GA and AD were found to vary linearly with their concentrations
in the range of 0.03–600 mM; 0.8–400 mM and 5.0–500 mM with detection limits of 0.009 mM, 0.4 mM
and 1.0 mM, respectively. The N-4-HP-DNBA/MgO/NPs/CPE was used for the determination of CA, GA,
and AD in capsule and pharmaceutical serum samples.
