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The characterisation of cannabis plants, especially the determination of specific phytocannabinoids, has gained enormous importance in the last decade, mainly due to the recent changes in cannabis control in several countries or states. This is particularly relevant for the forensic, medical or recreative industry to have a rapid, inexpensive, and reliable methodology to identify and quantify phytocannabinoids. Furthermore, spiking cannabis products with Δ 8 -tetrahydrocannabinol (THC) is a contemporary trend that demands improving or replacing current methods to include this cannabinoid. The current study presents an ultrasound-assisted solid-liquid extraction followed by high-performance liquid chromatography with diode array detection (HPLC-DAD) methodology to identify and quantify Δ 9 -THC, Δ 8 -THC, cannabidiol, cannabinol, Δ 9 -tetrahydrocannabinolic acid and cannabidiolic acid in cannabis products. The herbal samples were extracted with ethanol:acetonitrile (50:50, v:v) by ultrasonication using only 50 mg of sample. The plant oils were diluted in ethanol. The optimised procedure allowed ≈100% extraction efficiency of the target cannabinoids. The validation assays showed that the method is linear (R 2  > 0.997), selective, sensitive, precise and accurate, with suitable limits of detection (0.125-0.250 µg mL -1 ) and quantification ( 0.500 µg mL -1 ). The method was successfully applied to cannabis samples, demonstrating its suitability for routine analyses. This contribution follows the current demand for fast and straightforward analysis services of this plant and its derivatives, using small amounts of sample. The present study compares very favourably against other works, particularly in regards to the extraction efficiency, speed of the overall procedure, method sensitivity, and ability to monitor Δ 8 -THC spiked samples using a novel solvent mixture., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Self-association constants for the flavylium cations of the six most common anthocyanidin 3-glucosides were determined by circular dichroism (CD) and UV-Vis spectroscopy. Along with previous (1)H NMR results, all measurements were consistent with a monomer-dimer model. The CD spectra of the anthocyanidin 3-glucosides were similar to the analogues 3,5-diglucosides. All dimers of the anthocyanidin 3-glucosides exhibited left-handed CD signals, with petunidin-3-glucoside and myrtillin having the most intense signals. In addition, the magnitude of the molar ellipticity, [θ], was generally higher for the 3-glucosides than for the 3,5-diglucosides. For all six anthocyanins studied, the CD absorption spectra of their dimers showed evidence of the splitting of the monomer absorption into lower (J aggregates) and higher (H aggregates) energy bands. The angle and the distance between the dipolar moments of the two monomers comprising the dimer were obtained from the lower energy absorption band. While the angle was more or less similar in all six dimers, the separation distance between the monomer dipole moments differed dramatically. The intensity of the CD signal displayed a linear dependence with the inverse square of the dipole moment distances., (Copyright © 2012 Elsevier Ltd. All rights reserved.)