Supercritical Fluid Chromatography and High-Performance Liquid Chromatography/Tandem Mass Spectrometric Methods for the Determination of Cytarabine in Mouse Plasma

• Published in: Analytical chemistry (Washington) Vol. 79; no. 10; pp. 3856 - 3861
• Main Authors: Hsieh, Yunsheng, Li, Fangbiao, Duncan, Christine J. G
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 15.05.2007
• Subjects: Analytical chemistry; Animals; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography; Chromatography, High Pressure Liquid; Chromatography, Supercritical Fluid - methods; Cytarabine - blood; Cytarabine - isolation & purification; Drugs; Exact sciences and technology; Mass spectrometry; Mice; Other chromatographic methods; Plasma; Reproducibility of Results; Rodents; Sensitivity and Specificity; Spectrometric and optical methods; Tandem Mass Spectrometry - methods; Performance evaluation; Plasma; Ammonium; Chemical analysis; Atmospheric pressure; Internal standard; Carbon dioxide; HPLC chromatography; Selectivity; Silica; Supercritical fluid chromatography; Additive; Cytarabine; Efficiency; Polarity; Methanol; Stability; Rodentia; Ion pair; Acetate; Chemical ionization; Vertebrata; Reversed phase chromatography; Chemical modification; Sensitivity; Mammalia; Mouse; Reproducibility; Linearity; Mass spectrometry MS/MS; Graphite; Column chromatography; Mass spectrometry; Packed column
• ISSN: 0003-2700; 1520-6882
• DOI: 10.1021/ac062441s

The separation of cytarabine (ara-C) from the endogenous compounds in mouse plasma by packed-column supercritical fluid chromatography (pSFC) was achieved on bare silica stationary phase with an isocratic mobile phase composed of CO2/methanol solvent with addition of ammonium acetate. SFC is commonly assumed to be only applicable to nonpolar and relatively low-polarity compounds. In this work, a broader range of compound polarities amenable to pSFC with appropriate mobile-phase modifiers and additives under normal-phase retention mechanism was demonstrated. The pSFC was integrated with an atmospheric pressure chemical ionization source and a tandem mass spectrometer (MS/MS) to enhance the sensitivity, selectivity, and speed of the assay. The influence of mobile-phase components on chromatographic performance and ionization efficiency of the test compounds was investigated for improving the sensitivity and separation for the analyte and the internal standard. The pSFC−MS/MS approach requiring ∼2.5 min/sample for the determination of ara-C at nanograms per milliliter in mouse plasma was partially validated with respect to stability, linearity, and reproducibility. The mouse plasma levels of ara-C obtained by the pSFC−MS/MS method were found to be consistent with those determined by various reversed-phase, high-performance liquid chromatography methods using a porous graphite carbon column, a mixed-mode column, or a C18 column in conjunction with an ion-pairing agent coupled to a tandem mass spectrometer.