title: Quantitative analysis quantitation of 2-n-nonyl-1,3-dioxolane by stable-isotope dilution gas chromatography-mass spectrometry.
abstract: We report here a quantitative methodology developed for determination of SEPA (2-n-nonyl-1,3-dioxolane) in human serum. The method employed solid-phase extraction of SEPA and internal standard, [13C2]SEPA, from serum followed by gas chromatography-mass spectrometry analysis using EI monitoring m/z 73 and 75. We have investigated the utility of stable isotope dilution gas chromatography-mass spectrometry (GC-MS) for the determination of SEPA concentrations in serum using chemical ionization (positive ion, CI) or electron ionization (EI). The comparison of the specificity and sensitivity between EI and CI indicated that monitoring the m/z 73 ion in EI was superior to monitoring either MH+ or m/z 73 using CI. The method was simple, sensitive and accurate, demonstrating a lower limit of quantitation (LLOQ) of 0.25 ng/ml and intra- and inter-assay accuracy and precision of < or = 7.5%.
authors.affiliation: Drug Metabolism Research, Pharmacia and Upjohn, Kalamazoo, MI, USA.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Zhong
authors.forename: P E
authors.initials: PE
authors.lastname: Sanders
authors.forename: M J
authors.initials: MJ
authors.lastname: Hauer
authors.forename: J J
authors.initials: JJ
authors.lastname: Vrbanac
mesh_terms: D000277:Adjuvants, Pharmaceutic / Q000008:administration & dosage / Q000032:analysis*; D000287:Administration, Topical; D002247:Carbon Isotopes; D004148:Dioxolanes / Q000097:blood*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007201:Indicator Dilution Techniques; D008914:Minoxidil / Q000008:administration & dosage / Q000097:blood; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D000277:Adjuvants, Pharmaceutic; D002247:Carbon Isotopes; D004148:Dioxolanes; C111109:2-n-nonyl-1,3-dioxolane; D008914:Minoxidil