title: Sensitive and rapid liquid chromatography/tandem mass spectrometric assay for the quantification of piperaquine in human plasma.
abstract: A simple, sensitive and rapid liquid chromatography/tandem mass spectrometric (LC-MS/MS) method was developed and validated for quantification of piperaquine, an antimalarial drug, in human plasma using its structural analogue, piperazine bis chloroquinoline as internal standard (IS). The method involved a simple protein precipitation with methanol followed by rapid isocratic elution of analytes with 10mM ammonium acetate buffer/methanol/formic acid/ammonia solution (25/75/0.2/0.15, v/v) on Chromolith SpeedROD RP-18e reversed phase chromatographic column and quantification by mass spectrometry in the multiple reaction monitoring mode (MRM). The precursor to product ion transitions of m/z 535.3-->288.2 and m/z 409.1-->205.2 were used to measure the analyte and the IS, respectively. The assay exhibited a linear dynamic range of 1.0-250.2 ng/mL for piperaquine in plasma. The limit of detection (LOD) and lower limit of quantification (LLOQ) in plasma were 0.2 and 1.0 ng/mL, respectively. Acceptable precision and accuracy (+/-20% deviation for LLOQ standard and +/-15% deviation for other standards from the respective nominal concentration) were obtained for concentrations over the standard curve ranges. A run time of 2.5 min for a sample made it possible to achieve a throughput of more than 400 plasma samples analyzed per day. The validated method was successfully applied to analyze human plasma samples from phase-1 clinical studies. The mean pharmacokinetic parameters of piperaquine following 1000 mg oral dose: observed maximum plasma concentration (Cmax), time to maximum plasma concentration (Tmax) and elimination half-life (T1/2) were 46.1 ng/mL, 3.8h and 13 days, respectively.
authors.affiliation: Metabolism and Pharmacokinetic Department, Ranbaxy Research Laboratories, Plot # 20, Sector-18, Udhyog Vihar Industrial Area, Gurgaon, Haryana 122015, India.
authors.forename: Puran
authors.initials: P
authors.lastname: Singhal
authors.forename: Ashwani
authors.initials: A
authors.lastname: Gaur
authors.forename: Anirudh
authors.initials: A
authors.lastname: Gautam
authors.forename: Brijesh
authors.initials: B
authors.lastname: Varshney
authors.forename: Jyoti
authors.initials: J
authors.lastname: Paliwal
authors.forename: Vijay
authors.initials: V
authors.lastname: Batra
mesh_terms: D000962:Antimalarials / Q000097:blood*; D002853:Chromatography, Liquid / Q000379:methods*; D006801:Humans; D011804:Quinolines / Q000097:blood*; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013997:Time Factors; D010879:Piperazines
chemical_list: D000962:Antimalarials; D011804:Quinolines; C034759:piperaquine; D010879:Piperazines