Trace level determination of enantiomeric monoterpenes in terrestrial plant emission and in the atmosphere using a beta-cyclodextrin capillary columncoupled with thermal desorption and mass spectrometry

For the first time, enrichment on solid sorbents followed by thermal desorp tion has been used for the determination of the enantiomeric signature of m onoterpenes in the gaseous emission of terrestrial plants. A beta -cyclodex trin capillary column has been used for the separation of critical pairs. T he temperature program and column loading were optimized for making the acc urate quantification of individual enantiomers possible by mass spectrometr y. The resolution achieved was sufficient for separating enantiomeric monot erpenes from other biogenic and anthropogenic volatile organic compounds pr esent in air and vegetation emission samples. The method has been applied t o the determination of the enantiomeric ratios of monoterpenes in the gaseo us emissions of some evergreen plants and in the open atmosphere. (C) 2001 Elsevier Science B.V. All rights reserved.