MASS MEASUREMENTS BY AN ACCURATE AND SENSITIVE SELECTED-ION RECORDINGTECHNIQUE

Trace-level components of mixtures were successfully identified or con firmed by mass spectrometric accurate mass measurements, made at high resolution with selected ion recording, using GC and LC sample introdu ction. Measurements were made at 20 000 or 10 000 resolution, respecti vely. Under these conditions, accurate mass determinations from magnet or accelerating potential-electrostatic sector scans would not be fea sible. Chlorinated diphenyl sulfides, aralkylamine lubricant additives , and a sulfonated azo dye were analyzed with mass measurement errors of less than 5 ppm.