A simple HPLC method for quantitation of enalaprilat

Area of Science:

• Analytical Chemistry
• Pharmaceutical Analysis

Background:

• Enalaprilat is the active metabolite of enalapril, a widely used angiotensin-converting enzyme (ACE) inhibitor.
• Accurate quantification of enalaprilat is crucial for pharmacokinetic studies and therapeutic drug monitoring.

Purpose of the Study:

• To develop and validate a selective and sensitive reversed-phase high performance liquid chromatography (HPLC) method for the determination of enalaprilat.
• To establish the linearity, accuracy, precision, and sensitivity of the developed HPLC method.

Main Methods:

• Reversed-phase high performance liquid chromatography (RP-HPLC) with UV detection.
• Method validation including linearity, accuracy, precision (intra- and inter-day variation), limit of detection (LOD), and limit of quantitation (LOQ).
• Assessment of method selectivity by resolving enalaprilat from enalapril maleate.

Main Results:

• The HPLC method demonstrated linear response over a wide concentration range (1-200 µg/mL).
• High average accuracy (97.35 ± 4.93%) and acceptable intra-day (3.72%) and inter-day (5.18%) variations were achieved.
• The method exhibited excellent sensitivity with LOD of 0.125 µg/mL and LOQ of 0.5 µg/mL.
• The method showed selectivity, effectively separating enalaprilat from enalapril maleate peaks.

Conclusions:

• A robust and validated RP-HPLC method for enalaprilat determination has been successfully developed.
• The method is suitable for accurate, precise, and sensitive quantification of enalaprilat in analytical and potentially biological samples.
• The established selectivity ensures reliable analysis in the presence of related compounds like enalapril maleate.