Chemiluminescence detection of cannabinoids and related compounds with acidic potassium permanganate

Abstract

This is the first report of chemiluminescence from the reaction of cannabinoids with acidic potassium permanganate, which we have applied to the high performance liquid chromatography (HPLC) determination of cannabidiol (CBD) in industrial-grade hemp. The intensities of the light-producing reactions with two commercially available cannabinoid standards were compared to that of seven model phenolic analytes. Resorcinol, representing the parent phenolic moiety of the cannabinoid class, was shown to react with the permanganate reagents in a manner more similar to phenol than to its hydroxyphenol positional isomers, pyrocatechol and hydroquinone. Alkyl substituents on the phenolic ring, however, have a considerable impact on emission intensity that is dependent upon the position of the groups and the composition of the permanganate reagent. This analytical approach has potential for the determination of other cannabinoids including Δ(9) -tetrahydrocannabinol in drug-grade cannabis.

Research on psychedelic substances

“…This method is based on the reaction with acidic potassium permanganate and includes an application to the determination of cannabidiol (CBD) in industrial-grade hemp which highlights the opportunity to extend this approach to other cannabinoids. [34] This multidisciplinary Special Issue follows on from two issues previously published in Drug Testing and Analysis dedicated to the topic of psychoactive substances: New Psychoactive Substances (July/August 2011) and Illicit Drugs (September 2011). The editors are grateful to Prof. Mario Thevis and Paul Trevorrow for their kind help and support and are indebted to the contributing authors for their submission and to the reviewers for scrutiny.…”

Chemiluminescence Evidence Supporting the Selective Role of Ligands in the Permanganate Oxidation of Micropollutants

“…Although not discussed in the above studies, under certain conditions the reduction of permanganate elicits an emission of red light from the Mn(II) product of the reaction ( 4 T 1 → 6 A 1 transition), − which has been exploited for the detection of many organic and inorganic compounds . Recent investigations into this somewhat unrelated use of permanganate − have several intriguing similarities to those of the oxidation of micropollutants. ,, Many of the compounds known to produce an intense emission with permanganate possess phenolic functionality, and single-electron transfer to the Mn(III) precursor to form the emitter has been identified as a key reaction step. , Consequently, the chemiluminescence emission is generally enhanced by reaction conditions that favor the formation of Mn(III), including the presence of stabilizing agents such as phosphate oligomers and the preliminary partial reaction of permanganate with reductants such as Mn(II) or thiosulfate. , Herein, we examine the light producing reactions of permanganate with micropollutants under a range of chemical conditions, which presents not only a novel application of this chemiluminescence system but also an entirely new approach to explore the chemical oxidation of environmental micropollutants.…”