1993 Volume 9 Issue 2 Pages 245-249
Flash desorption and negative ion chemical ionization (NCI) mass spectrometry have been combined to study the detection of polycyclic aromatic hydrocarbons, such as benzo[a]pyrene, at high sensitivity. Such detection below pg orders can be readily accomplished by modifying the ionization chamber to increase the seal, and also by employing rapid heating of the sample loaded filament at a rate of 1000°C/s. This method enabled a several-fold sensitivity increase over both flash desorption with electron ionization and GC/MS with NCI. Furthermore, by setting the sampling points to 20 per second to cope with rapid ionization, a repeatability of within 10% was achieved, thereby allowing quantification utilizing an internal standard. Despite isomeric influences, simultaneous detection of homologs was also possible.
