https://pubs.acs.org/doi/10.1021/acssensors.9b00762

Comment; Artificial Intelligence meets nano-manufacturing to create something we’d only been able to dream of before, an accurate, hand-held “breathalyzer” that can detect THC levels.

  • Sean I. Hwang
  • Nicholas G. Franconi
  • Michael A. Rothfuss
  • Kara N. Bocan
  • Long Bian
  • David L. White
  • Seth C. Burkert
  • Raymond W. Euler
  • Brett J. Sopher
  • Miranda L. Vinay
  • Ervin Sejdic
  • Alexander Star*

Cite This:ACS Sens.2019482084-2093

Publication Date:July 19, 2019

https://pubs.acs.org/na101/home/literatum/publisher/achs/journals/content/ascefj/2019/ascefj.2019.4.issue-8/acssensors.9b00762/20190815/images/medium/se-2019-00762f_0007.gif

Copyright © 2019 American Chemical Society

Semiconductor-enriched single-walled carbon nanotubes (s-SWCNTs) have potential for application as a chemiresistor for the detection of breath compounds, including tetrahydrocannabinol (THC), the main psychoactive compound found in the marijuana plant. Herein we show that chemiresistor devices fabricated from s-SWCNT ink using dielectrophoresis can be incorporated into a hand-held breathalyzer with sensitivity toward THC generated from a bubbler containing analytical standard in ethanol and a heated sample evaporator that releases compounds from steel wool. The steel wool was used to capture THC from exhaled marijuana smoke. The generation of the THC from the bubbler and heated breath sample chamber was confirmed using ultraviolet–visible absorption spectroscopy and mass spectrometry, respectively. Enhanced selectivity toward THC over more volatile breath components such as CO2, water, ethanol, methanol, and acetone was achieved by delaying the sensor reading to allow for the desorption of these compounds from the chemiresistor surface. Additionally, machine learning algorithms were utilized to improve the selective detection of THC with better accuracy at increasing quantities of THC delivered to the chemiresistor.

Dr. Raymond Oenbrink