A Comprehensive Review of Analytical Methods for the Quantification of Selected ACE Inhibitors (Enalapril, Lisinopril, Ramipril and Perindopril) in Pharmaceutical and Biological Matrices

Abstract

Introduction: Hypertension is a major global health challenge, and the Renin–Angiotensin–Aldosterone System (RAAS) plays a crucial role in blood pressure regulation. ACE inhibitors act by blocking the conversion of angiotensin I to angiotensin II, thereby reducing vasoconstriction and peripheral resistance. Among them, Enalapril maleate, Lisinopril, Ramipril, and Perindopril are widely used due to their proven clinical efficacy and safety.

Physicochemical properties: The present section summarizes the key physicochemical properties of selected ACE inhibitors and highlights their analytical relevance in pharmaceutical evaluation. Physicochemical parameters such as molecular weight, solubility, lipophilicity, and structural features significantly influence drug stability, absorption, and chromatographic behaviour.

Methods: A comprehensive literature review was conducted to collect relevant data on the physicochemical properties of selected ACE inhibitors, namely Enalapril maleate, Lisinopril, Ramipril, and Perindopril. Information was gathered from official pharmacopoeias, peer-reviewed journal articles, standard reference textbooks, and published analytical reports. The collected data were critically evaluated and systematically compiled to compare molecular weight, solubility profile, lipophilicity, and structural characteristics, with emphasis on their analytical significance in pharmaceutical applications.

Results: The reviewed data indicate notable differences among the selected ACE inhibitors in terms of molecular weight, aqueous solubility, lipophilicity, and structural features. Enalapril maleate and Lisinopril exhibit higher aqueous solubility, whereas Ramipril and Perindopril demonstrate comparatively greater lipophilicity due to their ester functionalities. These variations significantly influence their stability profiles, chromatographic retention behaviour, and analytical method optimization. The findings highlight the importance of physicochemical characterization in selecting appropriate analytical conditions for reliable quantification.

Conclusions: The present review highlights the significance of physicochemical properties in understanding the analytical behaviour of selected ACE inhibitors. Variations in solubility, lipophilicity, molecular weight, and structural characteristics directly influence stability, chromatographic performance, and method development strategies. A systematic evaluation of these parameters supports the rational design and optimization of reliable analytical methodologies for pharmaceutical applications.