The illicit use of potent opioids poses a danger to users, law enforcement, and the public. Non-contact detection of vapors associated with hazardous drugs enables a safe and effective tool for their presumptive identification. Commercially available handheld ion mobility spectrometry (IMS) was utilized in the vaporous identification of fentanyl and related synthetic opioids. These research efforts sought to improve detection sensitivity using a novel preconcentrator. The goal of the research was to develop a highly sensitive method of non-contact field detection of illegal drugs by focusing on the detection of vaporous surrogate compounds that are representative of the majority of a given drug class (e.g. synthetic opioids). The proposed work provides a generalized analytical approach that is adaptable to other dangerous low volatility drug classes. As such, the possibility of expanding the utility of the instrument to include the detection of designer benzodiazepines (DBs) was explored.
The identification of volatile organic compounds (VOCs) associated with the drug class of interest allows for detection without manipulation of the dangerous substances. Prior efforts have already identified N-phenylpropanamide, NPP, and aniline as vapor surrogates of fentanyl-related opioids. Solid-phase microextraction (SPME) coupled with gas chromatography / mass spectrometry (GC/MS) was used to elucidate the vapor signature of DBs, although no compounds unique to the headspace signature of the DBs were determined.
To improve sensitivity metrics associated with IMS-based detection a functionalized Silicon Nanowire (SiNW) arrays for the preconcentration of vaporous compounds associated with the synthetic opioids was developed. Having already developed a method for coating SiNW arrays with acrylate-based polymers and established a library of coated devices, preconcentration efficiency was screened to identify the coating best suited for surrogate collection using the quartz crystal microbalance. Upon selection of optimal polymer, sorbent paper was coated with the selected polymer for an economical, simple, and robust method for the collection of VOCs from confiscated samples from a variety of crime labs. Use of this new collection method will be accessible to the inexperienced/untrained technician saving time and money while expanding the sampling pool of confiscated samples.