Sensitive and rapid quantification of the cannabinoid receptor agonist naphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-018) in human serum by liquid chromatography–tandem mass spectrometry☆
Introduction
Since a few years herbal blends have been sold as incense under the brand names “Spice”, “Smoke”, “Sence” and others. To our knowledge, these appeared in different parts of the world, such as Europe, America and Japan. The mixtures became very popular in the middle of 2008 in Germany and were available at head shops and on the Internet. There were claimed to be different varieties of a mixture of herbs (Canavalia maritima, Nymphaea caerulea, Scutellaria nana, Pedicularis densiflora, Leonotis leonurus, Zornia latifolia, Nelumbo nucifera and Leonurus sibiricus) which should produce cannabis like effects. Since December 2008, however, laboratory tests identified ingredients which were able to explain the ambiguous symptoms as an effect of synthetic cannabinoids. Therefore, “Spice” was proposed as a new product of designer cannabinoids. The analysis found several potent ingredients: naphthalen-1-yl-(1-pentylindol-3-yl)methanone (JWH-018), naphthalen-1-yl-(1-butylindol-3-yl)methanone (JWH-073) and 2-[(1R,3S)-3-hydroxycyclohexyl]-5-(2-methyloctan-2-yl)phenol (CP 47,497) along with its dimethyloctyl homologues and further chemical additives (tocopherol, oleamide) [1], [2], [3], [4]. In consequence of the investigations in January, 2009, JWH-018 and CP 47,497 were added to the German controlled drug schedules along with homologues [5].
Because of the growing popularity and the possible hazard potential, the analysis of “spice” ingredients becomes relevant in the field of forensic toxicology. However, reference substances for quantitative and qualitative investigations are rare, in Germany at the time of the current experiment only JWH-018 was commercially available.
Reported in the 1990s, JWH-018 belongs to a group of cannabimimetic indoles which acts as an agonist at cannabinoid receptors and shows the profile of cannabinoid effects in mice [6], [7], [8]. JWH-018 even acts as an agonist at cannabinoid receptors with a preference to the CB2 receptor. Compared to THC, a significant increase of binding affinity at cannabinoid receptors is described [9]. JWH-018 occurred in many of the “Spice” mixtures investigated and seems to be the only synthetic cannabinoid in “Smoke” [1].
The present study introduces a validated procedure for the detection of JWH-018 based on the tandem mass spectrometry. The method was used to examine the blood samples obtained after a self-experiment during which 2 test persons had smoked an incense of the specialty “Smoke”. To our knowledge, there currently exist no comparable published data on a validated procedure for the detection of JWH-018.
Section snippets
Analytical standards and reagents
HPLC-grade methanol was supplied by J.T. Baker (Deventer, The Netherlands). Ethyl acetate, hexane and sodium hydrogencarbonate were supplied by Merck (Darmstadt, Germany), ammonium acetate by Sigma-Aldrich (München, Germany), acetic acid by Riedel-de Haen, (Hannover, Seelze, Germany). JWH-018 and diazepam-d5 were obtained from LGC Promochem (Wesel, Germany).
Apparatus and conditions
An Applied Biosystems (Darmstadt, Germany) API 2000 tandem mass spectrometer equipped with ESI (Turboionspray®), a Shimadzu high pressure
Linearity and selectivity
Calibration curves were generated using linear regression for the quantifier MRM transition and found to be linear over the range investigated. The equations were y = 0.0994x + 0.0517 (R2 = 0.997). Blank samples did not yield any interference at the elution time for detection of JWH-018 and diazepam-d5.
Accuracy and precision
Results of the precision (expressed as %RSD) and the accuracy (expressed as % bias) studies are summarised in Table 2. The RSD values were between 2.4–4.8% (intra-day) and 13.5–14.8% (inter-day). The
Conclusions
The introduced method can be applied to detect JWH-018 in serum samples by means of LC/MS/MS. Using 2 MRM-transitions and in due consideration of the retention data, a safe forensic identification and quantification is possible up to the pg/ml concentration area. Since the identified active ingredients and several homologues were recorded in the German controlled drug schedules in January, 2009, the importance of Spice-products would probably have decreased. Overall, there hardly exist any data
References (13)
- et al.
Forensic Sci. Int.
(2009) - et al.
Bio. Med. Chem. Lett.
(1994) - et al.
Drug Alcohol Depend.
(2000) - et al.
Anal. Bioanal. Chem.
(2006) - et al.
J. Mass Spectrom.
(2009) - THC-Pharm GmbH, Frankfurt/Main, December...
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This paper is part of the special issue “Biological Monitoring and Analytical Toxicology in Occupational and Environmental Medicine”, Michael Bader and Thomas Göen (Guest Editors).