A Validated RP-HPLC Method for the Concurrent Quantification of Two Amlodipine-Based Ternary Mixtures With a Trio Color-Coded Sustainability Assessment

Abstract

Amlodipine (AML) is a dihydropyridine calcium channel antagonist that is extensively prescribed for the management of hypertension, either as monotherapy or in combination therapy. A trio-colored validated RP-high-performance liquid chromatography (HPLC) method was developed for the concurrent quantification of two AML-based ternary pharmaceutical preparations representing five different cardiovascular drugs with structural and thermodynamic divergence. The first mixture was AML, indapamide (IND), and perindopril (PER) (Mixture 1), and the second mixture was AML, hydrochlorothiazide (HCZ), and atenolol (ATN) (Mixture 2). Optimized chromatographic conditions were attained using the core–shell, endcapped Kinetex C18 column as the stationary phase, potassium dihydrogen phosphate buffer (50 mM, pH = 7.5):acetonitrile in ratio of 50:50 (v/v) as the mobile phase at 0.8 mL min−1 flow rate, and 215 nm as the UV detection wavelength. The developed method was validated in accordance with International Council for Harmonization (ICH) guidelines over linearity ranges of 1–60, 1–15, and 1–60 µg mL−1 for AML, IND, and PER, respectively, in Mixture 1, and 1–20, 1–100, and 1–200 µg mL−1 for AML, HCZ, and ATN, respectively, in Mixture 2 with regression coefficients (r2) greater than 0.9996 for all of the cited drugs. The developed method was successfully applied for determination of the cited drugs in laboratory-prepared mixtures and in pharmaceutical dosage forms with satisfactory recovery results. Moreover, greenness, blueness, and whiteness assessment were employed using Analytical GREEnness metric, Blue Applicability Grade Index, and Red Green and Blue model, respectively, demonstrating the environmental, practical, and sustainable efficiency of the developed method.