Application of Piezoelectric Sensors for the Determination of Aspartame in Fluids

A molecularly imprinted polymer (MIP) with an aspartame imprint is synthesized by noncovalent imprinting which is used to modify the surface of the electrode of a piezoelectric sensor. The values of the selectivity coefficients and imprinting factors of the developed MIP-E951 sensor in relation to target molecules and other sweeteners are calculated to confirm its ability to selectively detect aspartame. The range of determined concentrations is 1–1 × 10^–3 g/L; the detection limit of aspartame is 5 × 10^–4 g/L. When analyzing model solutions, it is found that foreign components usually present in soft drinks do not interfere with the determination of aspartame using the MIP sensor. The obtained results are compared with the data of the reference high performance liquid chromatography method: it is shown that the results of two methods are in a good agreement. The developed MIP sensor can be used for simple and rapid determination of aspartame in soft drinks.