Evaluation of green and practical analytical techniques for the determination of the antihypertensive drugs amlodipine and valsartan

The development of sustainable pharmaceutical analysis is essential to ensure drug safety, efficacy, and environmental responsibility. Amlodipine (AML) and valsartan (VAL) are widely prescribed antihypertensive agents often used in combination due to their synergistic effects on cardiovascular and renal health. This review presents a comparison of recent analytical methodologies developed for the quantification of AML and VAL in active pharmaceutical ingredients, dosage forms, and biological fluids. The techniques evaluated include ultraviolet-visible (UV–Vis) spectrophotometry, spectrofluorimetry, high-performance liquid chromatography (HPLC), micellar electrokinetic chromatography (MEKC), and ultra-high-performance liquid chromatography (UHPLC). Each method is critically assessed in terms of analytical performance and environmental sustainability, following the twelve principles of green analytical chemistry (GAC). To evaluate the environmental impact and practical applicability of the methods, three complementary assessment tools were applied: the analytical Eco-Scale, the analytical GREEnness metric (AGREE), and the blue applicability grade index (BAGI). The results indicate that while all reviewed techniques are capable of accurately quantifying AML and VAL, simpler methods such as UV–Vis and MEKC show higher green scores, whereas spectrofluorimetry and UHPLC offer greater sensitivity and speed. This work aims to guide researchers in selecting or developing analytical methods that balance performance, sustainability, and practical implementation in pharmaceutical analysis.