https://nij.ojp.gov/library/publications/using-sesame-seed-oil-preserve-and-preconcentrate-cannabinoids-paper-spray
Using Sesame Seed Oil to Preserve and Preconcentrate Cannabinoids for Paper Spray Mass Spectrometry...
This article presents a method for concentrating and preserving THC and synthetic cannabinoids in urine and oral fluid on paper for analysis by paper spray...