Specific adsorption and determination of aspartame in soft drinks with a zein magnetic molecularly imprinted modified MGCE sensor

In this work, an efficient and sensitive magnetic molecularly imprinted polymer with zein and deep eutectic solvents (ZDM-MIPs) was designed and synthesized to exclusively adsorb and detect aspartame (ASP). We used zein, together with deep eutectic solvents (DESs) and Fe3O4 as the cross-linker, functional monomer and support material, respectively. A magnetic glassy carbon electrode (MGCE) modified with ZDM-MIPs was used for selective recognition of ASP. The electrochemical response of the ZDM-MIPs-MGCE for quantification of ASP was evaluated with a portable electrochemical detection station with differential pulse voltammetry and cyclic voltammetry. The responses of ZDM-MIPs-MGCE signified a good linear relationship with ASP concentrations in the range of 0.1-50 μg mL-1. The sensor systems showed good accuracy and precision, with recovery percentages between 84% and 107%. These results suggested that the obtained ZDM-MIPs exhibited good adsorption performance for ASP in soft drinks, and this method could be used to determine ASP content in actual food samples.