Development of an instrument for the real-time (one second) detection of trace-level harmful substances under ambient pressure by high-resolution time-of-flight mass spectrometry using vacuum ultraviolet light photoionization

Abstract

Development of a real-time and high-resolution detection system for inspection of trace-level harmful substances at airports or stations is strongly required. A rapid sampling method and vacuum ultraviolet (VUV) light ionization time-of-flight mass spectrometry with high-resolution have been studied to enable 1 s detection. In order to get a high-resolution, the multi-turn type time-of-flight mass spectrometer (TOFMS) was selected. The maximum mass resolution of 6500 was attained for benzene molecular ion (m/z 78) generated by VUV light photoionization. In order to evaluate sensitivity of the real-time detection, trace-level 2,3-dimethyl-2,3-dinitrobutane (DMNB) and triacetone triperoxide (TATP) on stainless steel sheets were examined. Consequently DMNB was successfully detected within 1 s and the detection limit was 0.04 μg. Also TATP was successfully detected within 1 s and the detection limit was 0.2 μg.