Rapid voltammetric determination of maltol in some foods and beverages using a poly(methylene blue)/graphene-modified glassy carbon electrode

A novel poly(methylene blue)/graphene composite glassy carbon electrode was fabricated and the electrochemical behavior of maltol at the modified electrode was studied by cyclic voltammetry. In phosphate-buffered solution, the modified electrode exhibited excellent electrocatalytic activity towards the electrochemical oxidation of maltol. Under optimized conditions, the oxidation peak current showed a linear relationship with the concentrations of maltol in the ranges of 8.00 × 10 −7 to 4.00 × 10 −5 and 4.00 × 10 −5 to 5.40 × 10 −4  mol L −1 , with a detection limit of 6.50 × 10 −8  mol L −1 . The performance of the developed method was validated in terms of linearity ( r  = 0.9981 and 0.9955), recovery (97.0−99.3 %), reproducibility (relative standard deviations ≤ 3.1 %, n  = 6), and robustness. The method shows excellent sensitivity, selectivity, and reproducibility and has been successfully applied to analyzing maltol in a wide variety of food products.