Development of an electrochemical sensor for determination of vanillin in some food stuffs

A simple and cost-effective electrochemical sensor was developed for the determination of very low amounts of vanillin in various foodstuffs. Multi-walled carbon nanotubes (MWCNTs) modified glassy carbon electrode (GCE) beside differential pulse voltammetry (DPV) was applied for the measurement of vanillin. The effect of several variables on the voltammetric sensing of the vanillin, such as pH, buffer type and concentration, and the amount of MWCNTs were investigated. Using the optimized condition, the proposed sensor can detect vanillin in the concentration range from 4.15 to 294.12 µM with a correlation coefficient of 0.999, while the limit of detection is calculated to be 3.44 µM. Furthermore, to improve the detection sensitivity and detection of sub-micromolar levels of vanillin, the capability of the Adsorptive stripping differential pulse voltammetry (AdSDPV) technique was also studied. The detection limit improved to 8.51 nM using the stripping method. The developed sensor was successfully utilized for the determination of vanillin in some food samples such as ice cream and cake with desirable accuracy and recovery. Due to its simplicity and ability to detection of trace amounts, the proposed sensor can be easily used in quality control labs and industry tests to measure vanillin. Novelty impact statement Despite various methods reported on measuring vanillin, the proposed electrochemical sensor is very simple, cost-effective, and fast. This method can measure vanillin in a wide variety of foodstuffs with a lower limit of detection and is less prone to interferences from other possible compounds. Because of its simplicity and ability to detect trace amounts (nano-molar LOD), the proposed sensor has the capability of using in quality control laboratories and industrial tests for measuring vanillin.