Subject Area

Pharmaceutical Technology


Spectrophotometric analysis of the core drug while the coexistence of their toxic impurities is a vital analytical process. To date, there was no reported spectrophotometric method that have been reported for the simultaneous analysis of the two target drugs namely dimenhydrinate (DMH) and cinnarizine (CIN) in the presence of their most toxic impurities namely benzophenone (BZP) and 1- (diphenylmethyl)piperazine (DPP), respectively. In this study novel, green, accurate and timeless spectrophotometric analysis of a mixture of pharmaceutical drugs composed of DMH and CIN along with their toxic impurities BZP and DPP, respectively was successfully performed using smoothly applicable and costless spectrophotometric methods. Simple and easily manipulated spectrophotometric methods were introduced to simultaneously analyze the drug of interests in their pure forms, in market dosage form matrix and in prepared synthetic mixture along with their toxic impurities via ratio subtraction technique (RS) as an auxiliary resolution technique using dual wavelength (DW) method and constant multiplication (CM) method. The linearity range in all spectrophotometric methods for DMH was 6.0-60.0μg/mL while that for CIN was 3.0-30.0μg/mL. ICH guidelines were adhered in accordance with confirming validation of the presented methods where fulfilling results were accomplished. To assess the environmental impact, the Analytical Eco Scale (AES) is employed as a green evaluation tool, alongside the Green Solvent Selection Tool (GSST), the hexagon tool for sustainability assessment and Blue Applicability Grade Index (BAGI) tool. Application of these Greenness tools to the UV-spectrophotometric methods highlights their enhanced safety and efficiency in comparison with the costly, long-running, and laborious HPLC approach. This study proposes the incorporation of simple and green UV- spectrophotometric methods for conventional analysis in quality control of DMH and CIN containing formulations.