Rapid screening and identification of illicit drugs by IR absorption spectroscopy and gas chromatography

Anal. instruments based on IR Absorption Spectroscopy (IRAS) and Gas Chromatog. (GC) are today available only as bench-top instrumentation for forensic labs and bulk anal. Within the 'DIRAC' project funded by the European Commission, we are developing an advanced portable sensor, that combines miniaturized GC as its key chem. sepn. tool, and IRAS in a Hollow Fiber (HF) as its key anal. tool, to detect and recognize illicit drugs and key precursors, as bulk and as traces. The HF-IRAS module essentially consists of a broadly tunable External Cavity (EC) Quantum Cascade Laser (QCL), thermo-elec. cooled MCT detectors, and an IR hollow fiber at controlled temp. The hollow fiber works as a miniaturized gas cell, that can be connected to the output of the GC column with minimal dead vols. Indeed, the module has been coupled to GC columns of different internal diam. and stationary phase, and with a Vapor Phase Pre-concentrator (VPC) that selectively traps target chems. from the air. The presentation will report the results of tests made with amphetamines and precursors, as pure substances, mixts., and solns. It will show that the sensor is capable of analyzing all the chems. of interest, with limits of detection ranging from a few nanograms to about 100-200 ng. Furthermore, it is suitable to deal with vapors directly trapped from the headspace of a vessel, and with salts treated in a basic soln. When coupled to FAST GC columns, the module can analyze multi-components mixes in less than 5 min.