Ultraviolet absorption properties of synthetic cathinones

Abstract

Although many novel psychoactive drugs (NPSs) have emerged in the last decade, many of these drugs have not had their ultraviolet spectroscopic properties reported. Synthetic cathinones are one class of NPSs that such information is lacking. Properties such as maximum absorbance (λmax), molar absorptivity (ε) and specific absorbance (A11) are valuable for characterizing drugs. Specific absorbance (A11) is defined as the maximum absorbance of a 1% solution over a 1-cm path length as measured by ultraviolet–visible spectroscopy (UV–Vis). The determination of a reliable A11 is a useful alternative to quantitatively verify the concentration of analytical standard solutions. The UV spectral properties, λmax, ε, andA11, of 20 synthetic cathinones were determined in methanol using three different UV–Vis spectrophotometers. UV spectrophotometry can be used to distinguish between positional isomers of synthetic cathinones when the differences are substituted on the benzene ring. It can also be used to detect substitution at the para position of the aromatic ring and the addition of a 3,4-methylenedioxy function group on the aromatic ring of synthetic cathinones. This information can potentially be helpful to forensic chemists in an identification scheme for the analysis of synthetic cathinones in seized drugs.