Detection and identification of illicit drugs using terahertz imaging

Abstract

We demonstrated an advanced terahertz imaging technique for detection and identification of illicit drugs by introducing the component spatial pattern analysis. As an explanation, the characteristic fingerprint spectra and refractive index of ketamine were first measured with terahertz time-domain spectroscopy both in the air and nitrogen. The results obtained in the ambient air indicated that some absorption peaks are not obvious or probably not dependable. It is necessary and important to present a more practical technique for the detection. The spatial distributions of several illicit drugs [3,4-methylenedioxymethamphetamine, methylenedioxyamphetamine, heroin, acetylcodeine, morphine, and ketamine], widely consumed in the world, were obtained from terahertz images using absorption spectra previously measured in the range from 0.2to2.6THz in the ambient air. The different kinds of pure illicit drugs hidden in mail envelopes were inspected and identified. It could be an effective method in the field of safety inspection.

Investigation of (1R,2S)‐(−)‐Ephedrine by Cryogenic Terahertz Spectroscopy and Solid‐State Density Functional Theory

“…[9][10][11] To date, there has been limited work performed to gauge the applicability of THz spectroscopy as a tool for the detection and identification of concealed drugs, with the majority of the available work performed on illicit drugs and not drug precursors or related products. [2,3,12,13] The work presented here is of (1R,2S)-2-methylamino-1-phenylpropan-1-ol, (C 10 H 15 NO), more commonly known as (1R,2S)-(À)-ephedrine (ephedrine). The compound is a naturally occurring sympathomimetic amine, central nervous system stimulant, [14] and bronchodilator.…”

“…THz spectroscopy has seen use in a number of applications, including the detection of illicit drugs, [1][2][3] explosives, [4][5][6] and crystal polymorphs in pharmaceutical research. [7,8] The value of THz spectroscopy stems from the low-energy vibrations present in solid-state compounds and molecules that form the basis of a spectral "fingerprint" usable for identification, detection, and characterization.…”

Review of Terahertz Tomography Techniques

“…The main idea relies on the fact that molecular crystals present very specific features in the THz spectrum. For example, explosives [94][95][96][97] or illicit drugs [98][99][100] have been efficiently localized and unambiguously identified within an envelope [101], a parcel, or a suitcase [102]. Besides, dangerous metallic items like guns [103] or knifes become clearly visible by their shapes and can be easily identified by pattern recognition algorithm.…”

Copper Cobalt Magnetic Ceramic Materials Characterization at Terahertz Frequencies

“…THz frequencies may find use in medicine (Siegel 2004), as an alternative to X-rays in certain imaging applications (Hu and Nuss 1995), in security for detecting explosives (Shen et al 2005), in narcotics identification systems (Lu et al 2006), in bio-defense (Woolard et al 2003;Kemp 2011), in chemistry and biology for materials identification (Fischer et al 2005; Boss AFN, Migliano ACC, Wilke I Kiwa et al 2007), and other areas such as astronomy (Kulesa 2011;Smirnov et al 2012), space science (Siegel 2007), plasma physics (Tauk et al 2006), and aerospace applications (Petkie et al 2009;Chen 2007).…”