Simultaneous screening and quantification of 29 drugs of abuse in oral fluid by solid-phase extraction and ultraperformance LC-MS/MS.
BACKGROUND
The European DRUID (Driving under the Influence of Drugs, Alcohol And Medicines) project calls for analysis of oral fluid (OF) samples, collected randomly and anonymously at the roadside from drivers in Denmark throughout 2008-2009. To analyze these samples we developed an ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for detection of 29 drugs and illicit compounds in OF. The drugs detected were opioids, amphetamines, cocaine, benzodiazepines, and Delta-9-tetrahydrocannabinol.


METHODS
Solid-phase extraction was performed with a Gilson ASPEC XL4 system equipped with Bond Elut Certify sample cartridges. OF samples (200 mg) diluted with 5 mL of ammonium acetate/methanol (vol/vol 90:10) buffer were applied to the columns and eluted with 3 mL of acetonitrile with aqueous ammonium hydroxide. Target drugs were quantified by use of a Waters ACQUITY UPLC system coupled to a Waters Quattro Premier XE triple quadrupole (positive electrospray ionization mode, multiple reaction monitoring mode).


RESULTS
Extraction recoveries were 36%-114% for all analytes, including Delta-9-tetrahydrocannabinol and benzoylecgonine. The lower limit of quantification was 0.5 mug/kg for all analytes. Total imprecision (CV) was 5.9%-19.4%. With the use of deuterated internal standards for most compounds, the performance of the method was not influenced by matrix effects. A preliminary account of OF samples collected at the roadside showed the presence of amphetamine, cocaine, codeine, Delta-9-tetrahydrocannabinol, tramadol, and zopiclone.


CONCLUSIONS
The UPLC-MS/MS method makes it possible to detect all 29 analytes in 1 chromatographic run (15 min), including Delta-9-tetrahydrocannabinol and benzoylecgonine, which previously have been difficult to incorporate into multicomponent methods.
Section of Forensic Chemistry, Department of Forensic Medicine, University of Copenhagen, DK-2100, Denmark.
Nora
N
Badawi
Kirsten Wiese
KW
Simonsen
Anni
A
Steentoft
Inger Marie
IM
Bernhoft
Kristian
K
Linnet
D000701:Analgesics, Opioid / Q000032:analysis; D001569:Benzodiazepines / Q000032:analysis; D002853:Chromatography, Liquid / Q000379:methods*; D003042:Cocaine / Q000032:analysis; D013759:Dronabinol / Q000032:analysis; D006801:Humans; D012463:Saliva / Q000737:chemistry*; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods; D015813:Substance Abuse Detection / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
D000701:Analgesics, Opioid; D001569:Benzodiazepines; D013759:Dronabinol; D003042:Cocaine