Molecularly imprinted electrochemical sensor for highly selective and sensitive determination of artificial sweetener Acesulfame-K

The excess use of artificial sweeteners poses a serious issue to the environment and human health. Acesulfame-K (Ace-K) is a non-nutritive artificial sweetener excessively used as an alternative sugar substitute in various foods and beverages. Here a simple, selective and rapid method to determine Ace-K in dietary products is proposed. In this study, a molecularly imprinted polymer (MIP) based electrochemical sensor is designed for the sensitive and selective determination of Ace-K. MIP was developed by the electropolymerization of ortho-phenylenediamine (o-PD) thin film around template molecules (Ace-K) on a glassy carbon electrode. Various parameters such as deposition cycle, template removal and rebinding parameters were optimized for sensor fabrication. The sensor was characterized after each stage of fabrication using cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy (EIS) and atomic force microscopy (AFM) analysis. The MIP sensor exhibited wide linear range for the determination of Ace-K from 0.1 to 17.0 μM. The developed sensor attained the limit of detection (LOD) and limit of quantification (LOQ) of 0.35 µM and 1.2 µM, respectively. The applicability of the proposed sensor was examined for Ace-K determination in real samples. The MIP sensor exhibited excellent selectivity, repeatability, stability and commercialization potential for Ace-K detection.