Abbreviations: SCs, synthetic cannabinoids; Δ-9-THC, delta-9-tetrahydracannabinol; UHPLC, ultra high performance liquid chromatography; DAD, photodiode array; MS, mass spectrometry; GC, gas chromatography; DART, direct analysis in real time; TOF, time of flight spectrometry; NMR, nuclear magnetic resonance; ATR, attenuated total resonance; FTIR, fourier transform infrared spectrometry; TIC, total ion chromatogram; LC-MS/MS, liquid chromatography tandem mass spectrometry; CNS, central nervous system; LOD, limit of detection; LOQ, limit of quantitation; ULOL, upper limit of linearity; DUID, driving under the influence of drug; HLM, human liver microsomes; HPM, human pulmonary microsomes; CES 1, carboxylesterase 1
IntroductionSynthetic cannabinoids (SCs) are synthetic compounds sprayed on herbal products and have spread worldwide since 2004. Many of these compounds, more specifically l-valinamides and l-tert-leucinamides, are often characterized as part of the third, fourth and fifth generation of synthetic cannabinoids. There are many street names for herbal like compounds which are sprayed with these compounds, referred to as "Spice" such as Spice Diamond, Spice Gold, Spice Arctic Energy, Magic, Voodoo and Yucatan Fire. Such drugs are easily obtainable via the Internet, in smoke shops, and street markets. To evade law enforcement, these herbal incense products are often labeled "not for human consumption". Despite this, many countries have entered many synthetic cannabinoids to schedule 1.
1,2Initial reports of synthetic cannabinoids (SCs) in Unites States were in November 2008. In December 2008, German forensic laboratories initially identified JWH-018 and cannabicyclohexanol (CP-47,497 C8 homologue). The synthetic cannabinoids are frequently applied on plant material and inhaled. In January 2010, the popularity of these cannabinoids and their associated products appeared to have increased in the United States.3 Numerous SCs have been identified as adulterants, which have been seized by law enforcement. JWH-018, JWH-073, JWH-200, CP-47,497, and CP-47,497 C8 homologues were the first SCs identified as being abused. New generations of synthetic cannabinoids quickly emerged to evade law enforcement. After various laws were passed in the United States, different generations of SCs emerged varying only by slight modifications in structure. Some recent SCs include AB-CHMINACA and AB-PINACA. These substances are commonly marketed under the guise of being a ''legal high'' with a disclaimer of ''not for human consumption''. Law enforcement, public health officials, and clinicians are encountering cases in which there has been abuse of these substances, 4 requiring up to date information of the drug legislation, chemistry of the compounds and their detection, as well as the toxicology to be able to help identify these compounds when they present clinically.After the passage of the Synthetic Drug Abuse Prevent Act of 2012 in the United States, a third and fourth generation of SCs including UR-144, XLR11, and AKB-48 emerged...