Theoretical and electrochemical analysis of L-serine modified graphite paste electrode for dopamine sensing applications in real samples

In this study, we used the grinding modification approach to modify the carbon paste electrode (CPE) from an environmentally friendly catalyst (L-serine). L-serine(L-s) is shown to be an effective electrocatalytic at the modified CPE (MCPE) interface for detecting dopamine (DA). L-sMCPE showed excellent activity to detect DA in commercial injection samples with a recovery range of 98.9 to 100.5%. Theoretical studies were used to understand the electrocatalysis of L-serine at the atomic level using frontier molecular orbitals and analytical Fukui assay. The amine group of L-serine works as an extra oxidation site (cause for enhanced reduction peak DA) and a carboxylic acid group (reason for enhanced oxidation peak DA) at the L-sMCPE interface, according to our theoretical findings. Improvements to these processes might have a big influence on knowledge of the electrode interface for sensing applications.