Skip to main content

Cannabinoid stability in authentic oral fluid collected by expectoration and with the Quantisal™ device after controlled cannabis smoking

Wednesday, October 10, 2012 — Poster Session II

Noon – 2:00 p.m

Natcher Conference Center, Building 45




  • D Lee
  • G Milman
  • D.M. Schwope
  • A.J. Barnes
  • D.A. Gorelick
  • M.A. Huestis


Defining cannabinoid stability in authentic oral fluid (OF) is critically important for result interpretation. An expectorated OF pool and a pool of OF collected with Quantisal™ devices were prepared for each of 10 participants. ∆9-tetrahydrocannabinol (THC), 11-nor-9-carboxy-THC (THCCOOH), cannabidiol (CBD), and cannabinol (CBN) stability in 10 authentic expectorated and Quantisal-collected OF pools were determined after storage at 4°C for 1 and 4 wks and at -20°C for 4 and 24 wks. All Quantisal OF cannabinoids were stable for 1 wk at 4°C. After 4 wks at 4°C, as well as 4 and 24 wks at -20°C, THC was stable in 90, 80, and 80% and THCCOOH in 89, 40, and 50% of Quantisal samples, respectively. Cannabinoids in expectorated OF were less stable than in Quantisal samples when refrigerated or frozen. After 4 wks at 4 and -20°C, CBD and CBN were stable in 33-100% of Quantisal and expectorated samples; by 24 wks at -20°C, CBD and CBN were stable in ≤44%. Cannabinoid OF stability varied by analyte, collection method, storage duration and temperature, and across participants. OF collection with a device containing an elution/stabilization buffer, sample storage at 4°C, and analysis within 4 wks is preferred to maximize quantification accuracy.

back to top