Microwave-prepared surface imprinted magnetic nanoparticles based electrochemical sensor for adsorption and determination of ketamine in sewage

Detection technology for the determination of drugs, such as ketamine (KT), in sewage is of great significance in drug inspection and criminal investigation. Herein, we propose the utilization of ketamine magnetic molecularly imprinted polymers (Fe3O4@MIPs) as a target molecule identification and concentration container coupled with magnetic glassy carbon electrode (mGCE) for KT detection in sewage. Molecular simulations were employed to evaluate the most suitable monomer and ratio of functional monomer to template. Fe3O4@MIPs were prepared using microwave-assisted synthesis and possessed a "shell-core" structure with good recognition ability, superior adsorption capacity and fast kinetics toward KT. Additionally, a novel imprinted electrochemical sensor was constructed based on the magnetism of Fe3O4@MIPs for efficient monitoring of low concentrations of KT. The morphology and properties of Fe3O4@MIPs/mGCE were effectively characterized by element mapping, transmission electron microscopy, cyclic voltammetry and square wave voltammetry. KT detection was performed by square wave voltammetry within the range of 1.0 × 10-12 and 4.0 × 10-4 mol L-1, and the limit of detection was 8.0 × 10-13 mol L-1. Furthermore, Fe3O4@MIPs/mGCE was successfully tested for KT determination in domestic sewage samples.