Sustainable spectrophotometric resolution techniques for a spectrally overlapping mixture of Articaine Hydrochloride and Epinephrine Bitartrate with challenging formulation ratio

Abstract

Five clear and eco-friendly spectrophotometric methods were investigated to treat and amplify, accurately and precisely, the spectral signals of analyte concentrations that are deemed critical. The presented techniques were employed to simultaneously assess Articaine Hydrochloride (ART) and Epinephrine Bitartrate (EPI) in their authentic form and pharmaceutical formulation. Several challenges were encountered in the current study: spectra of the cited drugs were totally overlapped, and both drugs presented in their marketed formulation in a highly challengeable ratio of 4000:1 for ART and EPI, respectively. Additionally, no UV method had been reported to resolve the binary mixture in any matrices. The introduced techniques depended on the mixture's special spectral aspects, utilizing standard addition and spectrum addition techniques without any initial separation. Namely, they are factorized zero order absorption spectrum, dual wavelength, bivariate, constant extraction, and ratio difference methods. The proposed methods were validated according to the ICH guidelines and the results were found within the acceptable limits and linear over concentration ranges of 5–60 μg mL−1 for ART and 5–110 μg mL−1 for EPI. Furthermore, a statistical comparison of the observed data with the data from the official methods excluded any significant difference between the two results, and the same result was obtained using the one-way ANOVA. Adherence of the developed methods to green analytical chemistry (GAC) was assessed and compared with a published voltammetric method using national environmental methods index (NEMI), analytical eco-scale, green analytical procedure index (GAPI), and analytical greenness (AGREE) metric.