Standoff detection of fentanyl hydrochloride via nuclear quadrupole resonance: A multimodality pursuit

Michael W Malone; Harris E Mason; Adam R Altenhof; Michelle A Espy; Marc A Alvarez; Rami J Batrice; Amber J Day; Adam P Dioguardi; Michihiro Hirata; Margaret R Jones; Natalie E Klein; Ann E Mattsson; Shaun G Newman; Daniel A Rehn; Aaron M Tondreau; Kamal Wagle; Robert F Williams; Ruilian Wu; Michael T Janicke

doi:10.1093/pnasnexus/pgaf190

Standoff detection of fentanyl hydrochloride via nuclear quadrupole resonance: A multimodality pursuit

PNAS Nexus. 2025 Jul 1;4(7):pgaf190. doi: 10.1093/pnasnexus/pgaf190. eCollection 2025 Jul.

Authors

Michael W Malone¹, Harris E Mason², Adam R Altenhof¹, Michelle A Espy³, Marc A Alvarez⁴, Rami J Batrice⁴, Amber J Day^{5

6}, Adam P Dioguardi¹, Michihiro Hirata¹, Margaret R Jones², Natalie E Klein⁶, Ann E Mattsson⁷, Shaun G Newman¹, Daniel A Rehn⁷, Aaron M Tondreau², Kamal Wagle^{7

8}, Robert F Williams⁴, Ruilian Wu⁴, Michael T Janicke⁹

Affiliations

¹ Materials Physics & Applications - Quantum, MPA-Q, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
² Inorganic, Isotope, and Actinide Chemistry, C-IIAC, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
³ Nondestructive Testing & Evaluation, V-6, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁴ Biochemistry and Biotechnology, BTEK, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁵ Department of Statistics and Data Sciences, The University of Texas at Austin, Austin, TX 78712, USA.
⁶ Statistical Sciences, CCS-6, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁷ Computational Physics Division, XCP-5, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁸ Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
⁹ Nuclear and Radiation Studies Board, National Academy of Sciences, Washington, DC 20001, USA.

Abstract

Synthetic opioids, chiefly fentanyl, are responsible for nearly 70% of global annual drug deaths due to their extreme toxicity, ease of manufacture, and addictiveness. We show the magnetic resonance technique of nuclear quadrupole resonance (NQR) spectroscopy can be used for the standoff detection of fentanyl hydrochloride (HCl), likely the most common illicit synthetic opioid, even through opaque packaging such as cardboard, plastic, and glass. Combining work in synthesis, crystallography, density functional theory, and nuclear magnetic resonance, we report the electric field gradient tensor parameters of the $^{14}$ N and $^{35}$ Cl nuclei in fentanyl HCl to determine the chemically specific NQR frequencies. We directly observe the NQR signal for the aniline nitrogen and measure the associated relaxation times. The results show a robust ability for the standoff detection of relevant quantities of fentanyl HCl, at room temperature, with an inexpensive system.

Keywords: NQR; detection; fentanyl; synthetic opioids.

Published by Oxford University Press on behalf of National Academy of Sciences 2025.