Abstract
A sensitive, specific, and rapid liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method for the determination of lumefantrine (LF) and its metabolite desbutyl-lumefantrine (DLF) was developed and validated over a concentration range of 2–2000 ng/mL using 100 µL of plasma. After a simple solvent precipitation procedure, the samples were loaded onto Oasis HLB 1cc (30 mg) extraction columns. Separation was achieved using XTerra RP18 (2.1 mm × 100 mm, 5.0 µm) column with a binary gradient solvent system consisting of 0.1% formic acid in water (solvent A) and acetonitrile (solvent B). Mass detection was performed using a triple quadrupole mass spectrometer operating in positive electrospray ionization mode. The elution of LF (530.2→512.4), DLF (472.3→454.2) and HF (500.3→142.2) was monitored using multiple reaction monitoring. The extraction recovery of LF, DLF, and HF from human plasma was higher than 85%. The intra- and inter-day precision of LF, DLF, and HF were within 8.0% and the accuracy within ±9.0%. The method was applied to the determination of the concentrations of LF and DLF in patients infected with Plasmodium falciparum malaria on day 3 and 7 after treatment with Lumether.
ACKNOWLEDGMENTS
Thanks are due to Dr. N.C. Gupta for technical support and sampling. The authors sincerely acknowledge the financial support from the Department of Biotechnology, New Delhi.
Notes
*Precision RSD (%) = (SD/mean) × 100.
**Accuracy (%) = (mean measured concentration/nominal concentration) × 100.
*All QC samples were analyzed in triplicate. Mean values are reported.
Obs. = observed; Dev. = deviation.