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In this contribution two analytical devices for the fast detection of security-relevant substances like narcotics and explosives
are presented. One system is based on an ion trap mass spectrometer (ITMS) with single photon ionization (SPI).
This soft ionization technique, unlike electron impact ionization (EI), reduces unwanted fragment ions in the mass spectra
allowing the clear determination of characteristic (usually molecular) ions. Their enrichment in the ion trap and identification
by tandem MS investigations (MS/MS) enables the detection of the target substances in complex matrices at
low concentrations without time-consuming sample preparation. For SPI an electron beam pumped excimer light source
of own fabrication (E-Lux) is used. The SPI-ITMS system was characterized by the analytical study of different drugs
like cannabis, heroin, cocaine, amphetamines, and some precursors. Additionally, it was successfully tested on-site in a
closed illegal drug laboratory, where low quantities of MDMA could be directly detected in samples from floors, walls
and lab equipments. The second analytical system is based on an ion mobility (IM) spectrometer with resonant multiphoton
ionization (REMPI). With the frequency quadrupled Nd:YAG laser (266 nm), used for ionization, a selective
and sensitive detection of aromatic compounds is possible. By application of suited aromatic dopants, in addition, also
non-aromatic polar compounds are accessible by ion molecule reactions like proton transfer or complex formation. Selected
drug precursors could be successfully detected with this device as well, qualifying it to a lower-priced alternative
or useful supplement of the SPI-ITMS system for security analysis.
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