Determination of elemental composition of volatile organic compounds from Chinese rose oil by spectral accuracy and mass accuracy
Article first published online: 13 SEP 2011
Copyright © 2011 John Wiley & Sons, Ltd.
Rapid Communications in Mass Spectrometry
Volume 25, Issue 20, pages 3097–3102, 30 October 2011
How to Cite
Zhou, W., Zhang, Y., Xu, H. and Gu, M. (2011), Determination of elemental composition of volatile organic compounds from Chinese rose oil by spectral accuracy and mass accuracy. Rapid Commun. Mass Spectrom., 25: 3097–3102. doi: 10.1002/rcm.5194
- Issue published online: 13 SEP 2011
- Article first published online: 13 SEP 2011
- Manuscript Accepted: 20 JUL 2011
- Manuscript Revised: 19 JUL 2011
- Manuscript Received: 8 MAY 2011
Elemental composition determination of volatile organic compounds through high mass accuracy and isotope pattern matching could not be routinely achieved with a unit-mass resolution mass spectrometer until the recent development of the comprehensive instrument line-shape calibration technology. Through this unique technology, both m/z values and mass spectral peak shapes are calibrated simultaneously. Of fundamental importance is that calibrated mass spectra have symmetric and mathematically known peak shapes, which makes it possible to deconvolute overlapped monoisotopes and their 13C-isotope peaks and achieve accurate mass measurements. The key experimental requirements for the measurements are to acquire true raw data in a profile or continuum mode with the acquisition threshold set to zero. A total of 13 ions from Chinese rose oil were analyzed with internal calibration. Most of the ions produced high mass accuracy of better than 5 mDa and high spectral accuracy of better than 99%. These results allow five tested ions to be identified with unique elemental compositions and the other eight ions to be determined as a top match from multiple candidates based on spectral accuracy. One of them, a coeluted component (Nerol) with m/z 154, could not be identified by conventional GC/MS (gas chromatography/mass spectrometry) and library search. Such effective determination for elemental compositions of the volatile organic compounds with a unit-mass resolution quadrupole system is obviously attributed to the significant improvement of mass accuracy. More importantly, high spectral accuracy available through the instrument line-shape calibration enables highly accurate isotope pattern recognition for unknown identification. Copyright © 2011 John Wiley & Sons, Ltd.