An electrochemiluminescent sensor for phenolic compounds based on the inhibition of peroxydisulfate electrochemiluminescence

An electrochemiluminescent sensor for phenolic compounds based on the quenching effects of phenolic compounds on the electrogenerated chemiluminescence (ECL) of peroxydisulfate solution has been developed. Firstly, gold nanoparticles (AuNPs) were electrodeposited on the surface of glassy carbon electrode (GCE) for assembling l-cysteine (l-cys) through strong binding interactions between AuNPs and the functional groups of SH and NH2 of l-cys. Then, gold colloidal nanoparticles (nano-Au) and l-cys were assembled to achieve l-cys/nano-Au/l-cys/AuNPs film modified electrode. The ECL behavior of peroxydisulfate solution had been investigated in detail at the l-cys/nano-Au/l-cys/AuNPs/GCE, and phenolic compounds were found to be able to inhibit the ECL of peroxydisulfate solution. Based on this principle, an ECL sensor had been developed for detecting phenolic compounds. Due to the facts that both gold nanomaterials (AuNPs and nano-Au) and l-cys could promote the electron transfer and amplify the ECL signal of peroxydisulfate solution, the combination of them provided a rapid, simple and sensitive method for the detection of a series of phenolic compounds. The resulting sensor showed potential use in the pharmaceutical industry and environmental monitoring.