Kinetics and selectivity of permanganate chemiluminescence: A study of hydroxyl and amino disubstituted benzene positional isomers

Chemiluminescence detection of cannabinoids and related compounds with acidic potassium permanganate

“…Three dihydroxybenzene isomersresorcinol, hydroquinone, and pyrocatecholwere included for direct comparison to our previous study, [25] and because resorcinol represents the parent phenolic moiety of the cannabinoid class. resorcinol, [25] fenoterol, [27] and by extension, cannabinoids) with this reagent are similar to that of phenols without hydroxyl/amino groups. resorcinol, [25] fenoterol, [27] and by extension, cannabinoids) with this reagent are similar to that of phenols without hydroxyl/amino groups.…”

“…thiosulfate), or merged with the reagent on-line (e.g. formic acid or formaldehyde) to form a greater pool of Mn(III), which can enhance the chemiluminescence signal from the analyte; [25,27] hydroquinone, orcinol and olivetol were supplied by Sigma-Aldrich (NSW, Australia). Methanol, petroleum ether (40-60 C) and sulfuric acid (98%) were supplied by Merck (Vic, Australia).…”

“…[7,23] We recently gained insight into the vast differences in intensity elicited by different phenols and related compounds with this reagent by comparing the responses for nine hydroxyl/amino disubstituted benzene positional isomers. [25] In each case, the light-producing pathway of the meta-substituted compound was found to be far slower (resulting in much lower chemiluminescence intensities in flow analysis systems) than that of the ortho or para isomers. Furthermore, we have shown that an initial partial reduction of permanganate reagents can be used to generate relatively high concentrations of the key Mn(III) precursor to the emitter ( Figure 2), [26,27] resulting in considerable increases in reaction rates and chemiluminescence intensities.…”

“…Furthermore, we have shown that an initial partial reduction of permanganate reagents can be used to generate relatively high concentrations of the key Mn(III) precursor to the emitter ( Figure 2), [26,27] resulting in considerable increases in reaction rates and chemiluminescence intensities. [25][26][27] Considering that cannabinoids contain meta-substituted dihydroxybenzene groups or cyclic alkoxyl analogues (Figure 1), an examination of the chemiluminescence reactions of these and related compounds with permanganate offers not only a novel approach for their detection, but also a greater understanding of the relationship between analyte structure and chemiluminescence intensity with this widely utilized reagent. synephrine and tyrosine), or phenols with those substituents in the meta position (e.g.…”

“…resorcinol and fenoterol). [25][26][27] Considering that cannabinoids contain meta-substituted dihydroxybenzene groups or cyclic alkoxyl analogues (Figure 1), an examination of the chemiluminescence reactions of these and related compounds with permanganate offers not only a novel approach for their detection, but also a greater understanding of the relationship between analyte structure and chemiluminescence intensity with this widely utilized reagent.…”