Jump to main content
Jump to site search

Issue 13, 2012
Previous Article Next Article

Highly sensitive and selective analysis of urinary steroids by comprehensive two-dimensional gas chromatography combined with positive chemical ionization quadrupole mass spectrometry

Author affiliations

Abstract

Comprehensive two dimensional gas chromatography (GC × GC) provides greater separation space than conventional GC. Because of fast peak elution, a time of flight mass spectrometer (TOFMS) is the usual structure-specific detector of choice. The quantitative capabilities of a novel GC × GC fast quadrupole MS were investigated with electron ionization (EI), and CH4 or NH3 positive chemical ionization (PCI) for analysis of endogenous urinary steroids targeted in anti-doping tests. Average precisions for steroid quantitative analysis from replicate urine extractions were 6% (RSD) for EI and 8% for PCI-NH3. The average limits of detection (LODs) calculated by quantification ions for 12 target steroids spiked into steroid-free urine matrix (SFUM) were 2.6 ng mL−1 for EI, 1.3 ng mL−1 for PCI-CH4, and 0.3 ng mL−1 for PCI-NH3, all in mass scanning mode. The measured limits of quantification (LOQs) with full mass scan GC × GC-qMS were comparable with the LOQ values measured by one-dimensional GC-MS in selected ion monitoring (SIM) mode. PCI-NH3 yields fewer fragments and greater (pseudo)molecular ion abundances than EI or PCI-CH4. These data show that a benchtop GC × GC-qMS system has the sensitivity, specificity, and resolution to analyze urinary steroids at normal urine concentrations, and that PCI-NH3, not currently available on most GC × GC-TOFMS instruments, is of particular value for generation of structure-specific ions.

Graphical abstract: Highly sensitive and selective analysis of urinary steroids by comprehensive two-dimensional gas chromatography combined with positive chemical ionization quadrupole mass spectrometry

Back to tab navigation

Publication details

The article was received on 17 Jan 2012, accepted on 11 Apr 2012 and first published on 18 May 2012


Article type: Paper
DOI: 10.1039/C2AN35087D
Citation: Analyst, 2012,137, 3102-3110
  •   Request permissions

    Highly sensitive and selective analysis of urinary steroids by comprehensive two-dimensional gas chromatography combined with positive chemical ionization quadrupole mass spectrometry

    Y. Zhang, H. J. Tobias and J. T. Brenna, Analyst, 2012, 137, 3102
    DOI: 10.1039/C2AN35087D

Search articles by author

Spotlight

Advertisements