PMID- 9599579
OWN - NLM
STAT- MEDLINE
DCOM- 19980616
LR  - 20190717
IS  - 0003-2700 (Print)
IS  - 0003-2700 (Linking)
VI  - 70
IP  - 9
DP  - 1998 May 1
TI  - Determination of cannabinoids in water and human saliva by solid-phase 
      microextraction and quadrupole ion trap gas chromatography/mass spectrometry.
PG  - 1788-96
AB  - Solid-phase microextraction (SPME) is applied to the determination of 
      cannabidiol, delta 8-tetrahydrocannabinol (delta 8-THC), delta 
      9-tetrahydrocannabinol (delta 9-THC), and cannabinol in pure water and human 
      saliva. The inherent extraction behavior of the cannabinoids in pure water is 
      evaluated along with optimization of the method in human saliva. The commercially 
      available poly(dimethylsiloxane) (PDMS) SPME fibers were found to be the best 
      class for the cannabinoid analysis. Partition coefficients were found to be 
      extremely large for all of the cannabinoids (log K > 4.0). Equilibrium times for 
      the 7- and 30-micron PDMS fibers were 50 and 240 min, respectively. A shorter 
      extraction time of 10 min with the 30-micron PDMS fiber may be used for multiple 
      extractions from the same vial, thus conserving the sample necessary for analysis 
      and speeding up the total analysis time. Recoveries for the cannabinoids in 
      saliva, relative to pure water, were dramatically improved by a method developed 
      in our laboratory involving addition of glacial acetic acid to the sample vial 
      prior to performing SPME. Using this method, recoveries relative to SPME in pure 
      water ranged from 21 to 47% depending on the cannabinoid. The linear range for 
      spiked saliva samples was established at 5-500 ng/mL (r2 > 0.994) with precisions 
      between 11 and 20% RSD. The ultimate level of detection by SPME for the 
      cannabinoids in saliva was 1.0 ng/mL, with signal-to-noise values of > or = 12. A 
      saliva sample collected 30 min after marijuana smoking was subject to SPME and 
      traditional liquid-liquid extraction analysis. Internal standard quantitation 
      results for delta 9-THC by both methods yielded comparable results, indicating 
      that the SPME method of analysis is highly accurate and precise. The level of 
      delta 9-THC by SPME was found to be 9.54 ng/mL for the saliva sample.
FAU - Hall, B J
AU  - Hall BJ
AD  - Department of Chemistry and Biochemistry, University of Texas at Austin 
      78712-1167, USA.
FAU - Satterfield-Doerr, M
AU  - Satterfield-Doerr M
FAU - Parikh, A R
AU  - Parikh AR
FAU - Brodbelt, J S
AU  - Brodbelt JS
LA  - eng
PT  - Clinical Trial
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
PL  - United States
TA  - Anal Chem
JT  - Analytical chemistry
JID - 0370536
RN  - 0 (Cannabinoids)
RN  - 059QF0KO0R (Water)
RN  - 7J8897W37S (Dronabinol)
SB  - IM
MH  - Cannabinoids/*analysis
MH  - Dronabinol/analysis
MH  - Gas Chromatography-Mass Spectrometry
MH  - Humans
MH  - Marijuana Smoking/metabolism
MH  - Saliva/*chemistry
MH  - Substance Abuse Detection
MH  - Water/*analysis
EDAT- 1998/05/26 00:00
MHDA- 1998/05/26 00:01
CRDT- 1998/05/26 00:00
PHST- 1998/05/26 00:00 [pubmed]
PHST- 1998/05/26 00:01 [medline]
PHST- 1998/05/26 00:00 [entrez]
AID - 10.1021/ac971228g [doi]
PST - ppublish
SO  - Anal Chem. 1998 May 1;70(9):1788-96. doi: 10.1021/ac971228g.