Simple and ultrasensitive electrochemical sensor for oxalic acid detection in real samples by one step co-electrodeposition strategy.

ABSTRACT

Oxalic acid (OA), naturally available in vegetables and foodstuffs derived from them, easily combines with calcium and iron to form insoluble oxalates. Their chelation will result in various renal diseases; thus, the accurate determination of OA is quite significant in the evaluation of food quality and healthcare settings. Here, we developed an electrochemically induced alcohol-free sol-gel method to obtain platinum nanoparticles (PtNPs) adhered with porous silica on glassy carbon electrode (PSiO2-PtNPs/GCE) by a one-step process, which can be potentially used as an excellent catalyst towards electrochemical oxidation of OA for the first time. Without any redox mediator, PSiO2-PtNPs/GCE exhibited a low oxidation overpotential and a significantly high current signal, achieving a wide linear range of concentration from 0 to 45 µM and a detection limit as low as to 25 nM for OA detection. Moreover, this present alcohol-free sol-gel approach towards OA determination was verified in real samples, which is promising for foodstuff analysis and clinical diagnosis. Graphical abstract.