An electrochemically modified high-performance sensor for the voltammetric analysis and quantification of diabetes inducing alloxan in food samples

A sensitive and affordable sensor was designed for the detection of Alloxan (AXN) in food samples. Facile voltammetric techniques like linear sweep voltammetry (LSV), differential pulse voltammetry (DPV), and cyclic voltammetry (CV) were employed to study various parameters that influence the efficiency of the fabricated sensor. The exterior structural morphology of bare graphite paste sensor (BGPS) and the electrochemically functionalized poly(glycine)-modified graphite paste sensor (PGMGPS) was studied through Field emission scanning electron microscopy (FE-SEM). Electrochemical impedance spectroscopy (EIS) was applied to evaluate the active surface area of the working sensors. The optimum pH was determined to be 6.0 in phosphate buffer solution (PBS) of 0.2 M concentration. The analysis of potential scan rate variation revealed that the electro-oxidation of AXN on the electrode surface proceeds through diffusion-controlled kinetics with the transfer of two electrons. The limit of detection (LOD) were assessed to be 0.26 µM by CV, 0.24 µM by DPV, and 0.70 µM by LSV techniques, all exhibiting good linearity of oxidation peak current with the varied concentration of AXN. The developed sensor exhibited high selectivity and sensitivity toward the concurrent analysis with rutin (RTN), a flavonoid glycoside. The productivity of PGMGPS was noticed to be unaltered even in the presence of certain interfering metal ions. Furthermore, the stability, reproducible and repeatable attributes of the designed sensor were assessed and the obtained results are in accordance with the required limits. The performed analyses authenticate the proposed PGMGPS as reliable sensor for the quantification of AXN in food samples.