Magnetic solid phase extraction of rizatriptan in human urine samples prior to its spectrofluorimetric determination

A method has been developed and validated for the determination of rizatriptan drug in human urine samples. Magnetic solid phase extraction (MSPE) utilizing a molecularly imprinted nanoadsorbent was used as the sample preparation method for selective extraction of the drug molecules from the urine matrix prior to the spectrofluorometric determination of the drug at lambda(em) = 365 nm (lambda(ex) = 280 nm). The molecularly imprinted polymer (MIP) technique was used to improve the nanosorbent selectivity toward the drug molecules. The size, morphology, and structure of the synthesized MIP adsorbent were characterized by transmission electronic microscope, X-ray diffractometer, vibrating sample magnetometer, and FT-IR spectrometer. The nanoadsorbent was utilized to develop an MSPE method for selective extraction of the drug molecules in human urine samples prior to spectrofluorometric determination. The results showed that utilization of the MSPE step could provide a sensitive (limit of detection of 1.1 ng mL(-1)), precise (coefficients of variation < 2.21%), and accurate (recoveries > 97%) method for the spectrofluorometric determination rizatriptan drug in urine samples under the optimized conditions (pH, 8.0; adsorbent amount, 0.02 g; sorption time, 15 min; eluent, methanol: 1.0 mol L-1 acetic acid (1: 1 v/v); desorption time, 10 min). (C) 2017 Elsevier B.V. All rights reserved.