Type:
Journal
Description:
It would be beneficial to detect amphetamine-type stimulants (ATS) and precursors not only in a forensic lab, but also via field sensors. These would be used by customs and law enforcement units in their daily fight against the trafficking and street distribution of illicit drugs. Such sensors would need to combine hand-portability, high sensitivity, fast response, low false alarm rates, and robustness, together with the ability to analyze substances with a range of different chemo-physical characteristics, and to establish chemical similarities between an unknown substance—potentially a new ATS molecule—and a known set of drugs banned or controlled by law. Together, gas chromatography (GC) and IR absorption spectroscopy (IRAS) combine the chemical separation power of GC with the chemical identification ability associated with the analysis of molecular roto-vibrational transitions. GC-IRAS represents one of the most powerful techniques for the identification of amphetamines. 1 So far, however, GC-IRAS has been implemented essentially as bench-top instrumentation for forensic applications2 and ‘bulk’analysis. With ‘DIRAC’funding from the European Commission, 3 we are developing a GC-IRAS sensor that features hand-portability and fast response, together with the ability to analyze both bulk and traces, with nanogram-level sensitivity. 4 Sensitivity is greatly improved by matching the high radiation and spectral resolving power of a tunable external cavity-quantum cascade laser (EC-QCL), 5 with the very small interrogation volume (70l) of an IR hollow fiber (HF). 6 The HF-IRAS module is efficiently coupled to a silicon-micro-machined (SMM …
Publisher:
Publication date:
1 Jan 2013
Biblio References:
Origin:
SPIE Newsroom [Internet]