If a friend or, alternatively, a police undercover agent, gives you a tempting marijuana muffin, how can you know whether it’s made with real marijuana?
A report called Identification of Cannabinoids in Baked Goods by UHPLC/MS tells how to do it easily and directly – or as the professionals say, with “minimal sample preparation, and no chemical derivatisation”.
The two professionals who say this, Guifeng Jiang and Jason R Stenzel, cooked up the report for Thermo Fisher Scientific Inc, of San Jose, California. Jiang works for the company. Stenzel is part of Washington State Patrol’s Crime Laboratory Division in the remote town of Cheney.
By “minimal sample preparation”, Jiang and Stenzel mean minimal compared to the traditional method for testing the genuineness of leaf marijuana, hashish, hash oil, and what they lovingly call “residue collected from smoking paraphernalia”.
Their traditional method may not be your traditional method. Their traditional method, they explain, is gas chromatography-mass spectrometry, the professional forensic lab technician’s favourite way to identify the presence or absence of delta-9-tetrahydrocannabinol (THC), cannabinol and cannabidiol, the most famous ingredients of marijuana or hashish.
By “no chemical derivatisation”, Jiang and Stenzel mean without the rigamarole of doing chemical reactions that produce related substances which are easier to identify than the originals (the originals in this case being the aforementioned THC, cannabinol and cannabidiol).
Out with the old glitzy method, in with the new. Jiang and Stenzel prefer using ultra high-performance liquid chromatography with mass spectrometry (UHPLC/MS). As it happens, Thermo Fisher Scientific Inc manufactures UHPLC/MS equipment, one variety of which, the Accela UHPLC system, proved handy when Jiang and Stenzel decided to test their baked goods.
They are slightly coy when describing where they got the goods. “Brownie and cookie samples were obtained from evidence archived after adjudication” is all they say about it, other than vaguely muttering that it “was known to contain” THC, and that “after 10 years in the forensic laboratory’s training vault, cannabinoids in the cookie sample had degraded significantly”.
Jiang and Stetzel had some fun with those brownies and cookies. They crumbled them, added some methanol, vortexed the gooey mixture, allowed it to settle for two minutes, filtered it through a cotton-plugged Pasteur pipette, centrifuged it at 12,000 revolutions per minute for 90 seconds, then centrifuged it again.
Following this minimal sample preparation, they ran it through the ol’ Accela UHPLC system, and then through an MSQ Plus single quadrupole LC/MS detector that uses Thermo Fisher’s Xcalibur 2.05 software.
That’s pretty much the story of what they did – and what you can do, too, if you have this equipment on hand the next time someone gives you purportedly marijuana-containing cakes, breads, buns, doughnuts, tarts or pies.
(Thanks to Mark Dryfoos and Gary Dryfoos for bringing this to my attention.)
• Marc Abrahams is editor of the bimonthly Annals of Improbable Research and organiser of the Ig Nobel prize
– Article from The Guardian