In-Line Green Potentiometric Monitoring of Dissolution Behavior of Losartan Potassium Versus Pharmacopeial Methods: A Comparative Study

Abstract

Green electro-analytical method was developed and validated for quantitative determination and monitoring of the dissolution behavior of Losartan potassium tablets by in-line potentiometric measurement system with no need for pre-treatment or derivatization of the sample. A sensor was fabricated for in-line determination of Losartan potassium LOS in its dissolution medium utilizing polyvinyl chloride (PVC) based membrane and nitrophenyl octyl ether (NPOE) as a plasticizer. Tetraheptyl ammonium bromide (THAB) was employed as anion exchanger for the first sensor, while cetyltrimethylammonium bromide (CTAB) was used in the second sensor. The proposed method showed fast, stable near Nernstian responses across a relatively wide LOS concentration range (1.0 × 10−5 to 1.0 × 10−2 mol/L) in the case of THAB-based sensor while LOS concentration range was (1.0 x 10−4 - 1.0 × 10−2 mol/L) in case of CTAB-based sensor. The dissolution method was developed according to FDA regulations using USP apparatus II, 50 rpm rotation speed, at 37.0 ± 0.5°C and 900 mL of deareated double distilled water as the dissolution medium. Dissolution profile was generated over 45 min and compared to those obtained by the official spectrophotometric and HPLC methods. The developed method can be efficiently applied as benchtop real-time in-process analysis of LOS concentration. Greenness assessment using Analytical Eco-scale, National Environmental Method Index (NEMI), Green Analytical Procedure Index (GAPI) and Analytical Greenness (AGREE) calculator was conducted to evaluate and compare the proposed method with the official ones.