Selective quantification of diclofenac from groundwater and pharmaceutical samples by magnetic molecularly imprinted polymer-based sorbent coupled with the HPLC-PDA detection

Diclofenac (DCF) is a pharmaceutical contaminant of water bodies and therefore, improvement of analytical techniques for its removal and quantitation is one of the current interests of analysts. Herein, DCF selective magnetic molecularly imprinted polymer (MMIP) has been fabricated and characterized by Fourier transform-infrared spectroscopy, thermogravimetric analysis, vibrating scanning magnetometer, scanning electron microscopy, high-resolution transmission electron microscope, energy-dispersive X-ray spectroscopy, and Brunauer–Emmett–Teller analyzer. Furthermore, the protocol for the quantification of DCF using MMIP-HPLC-PDA combo has been optimized by investigating the effect of the amount of MMIP, type and volume of eluent, and variation of pH. The optimized protocol suggested a method detection limit of 0.042 ng mL −1 and linearity of results in the range 0.1–100 ng mL −1 ( R 2 = 0.99). The fabricated material offered recovery of DCF up to 96.38–99.46% from groundwater and pharmaceutical samples with a relative standard deviation of < 4%. In addition, the material was found selective and sensitive for DCF among its analogous drugs like mefenamic acid, ketoprofen, fenofibrate, aspirin, ibuprofen, and naproxen. Graphical abstract