Simultaneous determination of antidementia drugs in human plasma: Procedure transfer from HPLC–MS to UPLC–MS/MS

A previously developed high performance liquid chromatography mass spectrometry (HPLC–MS) procedure for the simultaneous determination of antidementia drugs, including donepezil, galantamine, memantine, rivastigmine and its metabolite NAP 226-90, was transferred to an ultra performance liquid chromatography system coupled to a tandem mass spectrometer (UPLC–MS/MS). The drugs and their internal standards ([2H7]-donepezil, [13C,2H3]-galantamine, [13C2,2H6]-memantine, [2H6]-rivastigmine) were extracted from 250 μL human plasma by protein precipitation with acetonitrile. Chromatographic separation was achieved on a reverse phase column (BEH C18 2.1 mm × 50 mm; 1.7 μm) with a gradient elution of an ammonium acetate buffer at pH 9.3 and acetonitrile at a flow rate of 0.4 mL/min and an overall run time of 4.5 min. The analytes were detected on a tandem quadrupole mass spectrometer operated in positive electrospray ionization mode, and quantification was performed using multiple reaction monitoring. The method was validated according to the recommendations of international guidelines over a calibration range of 1–300 ng/mL for donepezil, galantamine and memantine, and 0.2–50 ng/mL for rivastimgine and NAP 226-90. The trueness (86–108%), repeatability (0.8–8.3%), intermediate precision (2.3–10.9%) and selectivity of the method were found to be satisfactory. Matrix effects variability was inferior to 15% for the analytes and inferior to 5% after correction by internal standards. A method comparison was performed with patients’ samples showing similar results between the HPLC–MS and UPLC–MS/MS procedures. Thus, this validated UPLC–MS/MS method allows to reduce the required amount of plasma, to use a simplified sample preparation, and to obtain a higher sensitivity and specificity with a much shortened run-time.