A novel Au nanoparticles/ionic liquids/N- and P-co-doped carbon nanotubes-modified carbon cloth sensor for the sensitive detection of adrenaline

Adrenaline (AD) is important in information transmission through the human central nervous system. Considering the significant biochemical functions of AD, the development of electrochemical sensors capable of detecting AD levels in living organisms has attracted considerable interest. In this study, AD was detected using electrochemical sensors developed based on Au nanoparticles/ionic liquids/N- and P-co-doped carbon nanotubes-modified carbon cloth (AuNPs/ILs/N,P-MWCNTs/CC) electrodes. AuNPs/ILs/N,P-MWCNTs/CC composites were prepared on carbon cloth (CC) substrates using ionic liquids (ILs), N- and P-co-doped multi-walled carbon nanotubes (N,P-MWCNTs), and Au nanoparticles (AuNPs) as modified materials. The effects of pH and scanning speed were optimized and tested on the prepared composites. The results of cyclic voltammetry (CV) and differential pulse voltammetry (DPV) experiments showed that the modified ILs, N,P-MWCNTs, and AuNPs effectively improved the oxidation performance of AD. In addition, the linear range obtained from the DPV scans of the AuNPs/ILs/N,P-MWCNTs/CC composite material was 30–505 μmol/L, with a detection limit of 0.31 μmol/L. The fabricated sensors have good sensitivity (6.9 μA·mM⁻¹·cm⁻²) for AD of 30–505 μM. Therefore, the electrochemical sensing method based on the AuNPs/ILs/N,P-MWCNTs/CC composite material is a promising and reliable AD detection technology that also exhibits good selectivity in the presence of interfering substances such as folic acid and ibuprofen. In practical applications, this material can help realize real-time AD detection to determine whether athletes use doping and other illegal drugs before competitions and to perform synchronous detection.