Examination of North Dakota Plants by a Thin Layer Chromatographic Method Used to Identify Cannabis

Abstract

The plant Cannabis saliva L. is the source of the psychotomimetic drug preparations marijuana and hashish. Due to widespread use of these products, and criminal statutes restricting or prohibiting their possession and/or distribution, it is necessary that law enforcement agencies have a simple yet accurate screening procedure for the presence of Cannabis materials. De Faubert Maunder (1969) has developed a rapid and reasonably specific test for Cannabis in which the suspected material is extracted with petroleum ether, applied to filter paper, allowed to dry, and then treated with a solution of Fast Blue salt B (FBB). If Cannabis has been extracted, a red to violet color rapidly develops, De Faubert Maunder (1969) examined approximately 200 plant materials by this method and found nutmeg and mace, both products of Myristica frugruns Houtt., produced a false positive result. Other plant materials producing false positive results are Agrimony, with color of a much paler hue than that produced by Cannabis, and Henna if an excessively large sample is tested (de Faubert Maunder, 1969b). Thin layer chromatography coupled with Fast Blue salt B (FBB) visualization has been used to resolve the problem of false positives (Forrest and Heacock, 1974). However, when testifying in criminal cases, forensic chemists are often asked by defense attorneys if materials obtained from local plants are able to produce a false positive result when examined by thin layer chromatography and FBB visualization. To help resolve this question, petroleum ether extracts of leaves, flowers and stems prepared from 118 species of plants indigenous to North Dakota (U.S.A.) were examined by a thin layer chromatographic method used to identify Cannabis materials.