Electrochemical validation of L-tyrosine with dopamine using composite surfactant modified carbon nanotube electrode

Herein, for the first time, we employed sodium lauryl sulfate and Triton X-100 composite surfactants immobilized on the carbon nanotube paste electrode (STMCNTPE) as an electrochemical sensor for the electro-catalytic oxidation of L-tyrosine (L-Ty) and dopamine (DP) through cyclic voltammetry. The STMCNTPE exhibited a robust enhancement impact on the oxidation of L-Ty with enhanced current signal compared to other electrodes. In ideal conditions, various parameters were studied such as pH value, concentrations of surfactants, different ranges of sweep rates, the concentration of an analyte, simultaneous study, and the interference analysis. The proposed sensing film unveiled with a detection limit 3.75 × 10 –7 M and quantification limit 1.22 × 10 –6 M for a wide linear range. The STMCNTPE revealed with remarkable sensitivity, selectivity, long-term stability, good reproducibility and repeatability, biocompatible, enhanced electrode fouling resistance, and anti-interference. Finally, the sensing film STMCNTPE carried out successfully for the analysis of L-Ty in cow’s milk and pharmaceutical drug. Graphic abstract The novel electrode was developed by immobilization of composite surfactant ST was modified on carbon nanotube paste electrode (STMCNTPE) was utilized for validating the electrochemical oxidation of L-tyrosine using CV technique. The single quantified peak revealed to be irreversible carrying one electron and one proton transfer. The STMCNTPE was further studied simultaneously with DP. The proposed sensor was successfully validated on milk sample and pharmaceutical drug analysis. The STMCNTPE presented with good stability, reproducible and sensitive with low limit of detection 3.75 × 10 −7 .