Solid-phase extraction using a molecularly imprinted polymer for the selective purification and preconcentration of norfloxacin from seawater

Abstract

A highly selective and effective method for the purification and preconcentration of norfloxacin (NFX) in seawater samples was developed based on molecularly imprinted solid-phase extraction (MISPE). The molecularly imprinted polymer was synthesized by precipitation polymerization. Methacrylic acid (MAA) and ethylene glycol dimethacrylate (EGDMA) were used as the functional monomer and crosslinker, respectively. The resulting molecularly imprinted polymer (MIP) showed high adsorption for NFX and was selective for its solid-phase extraction. An offline MISPE method followed by high performance liquid chromatography with diode array detection was established for the determination of NFX in seawater. The recoveries of spiked seawater samples using the MISPE columns were satisfactorily higher than 77.6%. The relative standard deviation was less than 5.60%, and the limit of detection was 0.027 μg L−1. Four seawater samples obtained from the Bohai Sea were analyzed, and NFX was found only at one location at a concentration of 0.280 μg L−1.