A novel tyrosine electrochemical sensor based on poly 3,4-ethylene-dioxythiophene and gold nanoparticles

The amino acid tyrosine serves as a crucial precursor for neurotransmitters, playing a pivotal role in maintaining nitrogen balance within the human body, and deviations from optimal levels can significantly impact overall health status. In this study, we developed a novel green electrochemical sensor for tyrosine based on a composite of poly 3,4-ethylene-dioxythiophene (PEDOT) and gold nanoparticles (AuNPs), which was then applied to modify a glassy carbon electrode. The modified electrode underwent characterization using metallographic microscopy, scanning electron microscopy (SEM) and X-ray energy-dispersive analysis (EDAX). Moreover, cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS) were performed to describe the electrochemical behavior of tyrosine. Under the best experimental conditions, we achieved a linear detection range of 3 to 1000 mu M with a limit of detection at 1.8 mu M. In addition, interference studies along with assessments of stability, repeatability, and reproducibility were conducted on the sensor. Results demonstrated that the modified electrode effectively eliminated interference from tryptophan (Trp) and ascorbic acid (AA) while exhibiting excellent stability, repeatability, and reproducibility.