Comparison of the sensitivities of sixteen phenols in waters using an automated preconcentration system and gas chromatography/mass spectrometry in different ionization modes

✍ Scribed by M. A. Crespín; S. Cárdenas; M. Gallego; M. Valcárcel

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 173 KB
• Volume: 12
• Category: Article
• ISSN: 0951-4198
• DOI: 10.1002/(sici)1097-0231(19980227)12:4<198::aid-rcm139>3.0.co;2-0

✦ Synopsis

The analytical performances of the electron impact and chemical (positive and negative) ionization modes in the mass spectrometric identification and quantitation of phenols were studied simultaneously. Twenty phenols containing different substituents (viz. chloro, nitro, amino, alkyl and sulphonic groups) were initially tested, amino and sulfonic phenols being discarded after preliminary experiments. Samples containing phenols at the nanograms per millilitre level were preconcentrated by using a simple continuous solid-phase extraction system. Full-scan monitoring at a single m/z value for each analyte allowed the detection of the phenols at concentrations over the range 0.2-1.0 ng/mL in the electron impact mode and the ranges 1-20 and 10-35 ng/mL in the negative (NCI) and positive methane chemical ionization (PCI) modes, respectively. The lower sensitivity obtained with chemical ionization is offset by the valuable structural information it provides from adduct formation (PCI) or different fragmentation patterns (NCI) for isomers.