An ion‐pairing liquid chromatography/tandem mass spectrometric method for the determination of cytarabine in mouse plasma

Abstract

An ion‐pairing high‐performance liquid chromatographic (IP‐HPLC) system interfaced with an atmospheric pressure chemical ionization (APCI) source and a tandem mass spectrometer (MS/MS) with minimal sample preparation was developed for the determination of cytarabine (ara‐C), a very hydrophilic anticancer drug, in mouse plasma. A conventional reversed‐phase chromatographic column in combination with two ion‐pairing reagents was adapted for retention and separation of ara‐C from the endogenous interferences in mouse plasma. The effects of the experimental conditions such as the fraction of ion‐pairing reagents and organic solvents in the mobile phase on the chromatographic performance and the ionization efficiency of ara‐C were investigated. The potential of ionization suppression resulting from the endogenous biological materials on the IP‐HPLC/MS/MS method was evaluated using the post‐column infusion technique. Furthermore, the feasibility of the proposed IP‐HPLC/MS/MS procedure for analysis of ara‐C in the mouse plasma was demonstrated by comparison with those obtained by the porous graphite carbon column (PGC) HPLC/MS/MS method. Copyright © 2007 John Wiley & Sons, Ltd.