Identification of compounds and specific functional groups in the wavelength region 168-330 nm using gas chromatography with UV detection

A GC-UV instrumental set up with two different GC units has been used for d etermination of specific functional groups and compounds in complex mixture s. Separations have been made using a micro gas chromatograph built into a gas flow cell and by means of an external capillary gas chromatograph linke d to the same gas flow cell. Four various applications (cigarette smoke, pe troleum, dust, flavour) have been performed in order to demonstrate the pot ential of the GC-UV method. Gas phase UV spectra have been recorded in the region of 168-330 nm. Based on a gas phase spectrum reference library the i dentification of unknowns as well as the determination of specific function al groups have been achieved. A table showing the spectral shapes and posit ions of the absorption bands for 50 specific functional groups is presented . The advantage of using derivative spectra in order to amplify spectral de tails and improve selectivity is discussed. Regarding sensitivity, it has b een found that identifications can be made in the mid-pg range and limit of detection for naphthalenes are at a level of 0.5-3 pg/s. (C) 2000 Elsevier Science B.V. All rights reserved.