Advanced Au/SnS2 photoelectrochemical sensor for epinephrine detection in athletes' biological samples

Epinephrine (Ep) is an essential biomarker toward stress, physical activity, and metabolic response that is important for monitoring the health and performance of athletes. This study presents a new photoelectrochemical sensor (PEC) based on the deposition of a layer of gold nanoparticles (AuNPs) on the surface of a SnS 2 film coated on a conductive ITO substrate (Au/SnS 2 /ITO). Due to the PEC property of SnS 2 and the catalytic and conductive properties of AuNPs, the photoelectrochemical currents and sensitivity of the Au/SnS 2 /ITO sensor have been increased. The Au/SnS 2 /ITO sensor was fabricated using a simple hydrothermal method and electrochemical deposition process and characterized by different techniques. In obtained optimal conditions, the sensor showed a linear range of 50 nM to 160 µM with low detection limit 10.7 nM. Moreover, the Au/SnS 2 /ITO sensor acted with excellent stability (300 s), reproducibility (4.6 % of RSD), selectivity and lifetime (1 month), providing it suitable for repeated measurements of Ep in biological samples. The efficiency of the sensor was tested with human serum samples from athletes with excellent recovery from 99.5 % to 104.9 %, proving its potential as an applicable tool for monitoring of Ep, with values for sports science, health diagnostics, and personalized exercise training.