An eco-concerned development of a fast, precise and economical spectrophotometric assay for the antiviral drug simeprevir based on ion-pair formation

Simeprevir sodium (SMV) is one of the antiviral drugs used for the treatment of virus C. The current strategy develops and validates a new eco-concerned tool for its quantification in the pure and pharmaceutical formulations. Sulfonephthalein acid dyes were used for this purpose, applying visible analyses based on ion-pair formation. A linear relation between the absorbed signal and the drug concentration is obtained up to 67.0 μg mL-1 with r2 of 0.9989-0.9999. The measurement is carried out at 410, 415, 410, and 403 nm for bromocresol green, bromoxelenol blue, bromothymol blue, and bromocresol purple, respectively, in dichloromethane as a solvent. The drug structure was confirmed utilizing different tools; mass spectrometry, FT-IR, 1H NMR, and thermal analysis. Association, formation constants, molar absorptivity, and free energy change for SMV-ion-pairs were calculated. The limit of detection reaches 50.0 ng mL-1 with a quantification limit of 180.0 ng mL-1. The recovery values are 96.44-104.39%, with a relative standard deviation 0.15-1.37%. For confirmation of the obtained results, they were statistically compared with a previously published HPLC method utilizing t-and F-tests. © 2021 by the authors.