Preparation, characterization, and analytical application of ramipril membrane-based ion-selective electrode

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Materials Science

Background:

• Ramipril is a widely prescribed medication for cardiovascular conditions.
• Accurate quantification of ramipril in pharmaceutical formulations is crucial for quality control and patient safety.
• Development of selective and sensitive electrochemical sensors can improve drug analysis.

Purpose of the Study:

• To fabricate and electrochemically evaluate novel PVC membrane-based ion-selective electrodes (ISEs) for ramipril.
• To assess the performance of ISEs utilizing ramipril-ion-pair complexes as sensing materials.
• To determine the suitability of these ISEs for the quantitative analysis of ramipril in pharmaceutical products.

Main Methods:

• Fabrication of PVC membranes incorporating ramipril-phosphomolibdate and ramipril-tetraphenylborate ion-pair complexes.
• Electrochemical characterization of the developed ion-selective electrodes using potentiometry.
• Evaluation of electrode sensitivity, linearity, detection limit, and operational concentration range.
• Validation of electrode performance by analyzing ramipril in pharmaceutical formulations via direct potentiometry.

Main Results:

• Developed two types of PVC membrane ion-selective electrodes responsive to ramipril.
• Electrodes exhibited near-Nernestian responses with sensitivities of 53-54 mV/decade over a concentration range of 1.0 x 10⁻² to 1.0 x 10⁻⁵ mol L⁻¹.
• Achieved low detection limits for ramipril, ranging from 3.0 x 10⁻⁶ to 4.0 x 10⁻⁶ mol L⁻¹.
• Successfully applied the electrodes for direct potentiometric determination of ramipril in pharmaceutical formulations with high average recovery (>96%) and low standard deviation (<3%).

Conclusions:

• The developed PVC membrane ion-selective electrodes are effective for sensitive and selective detection of ramipril.
• These electrodes provide a reliable and accurate method for the potentiometric determination of ramipril in pharmaceutical samples.
• The proposed electrochemical sensors offer a promising alternative for routine quality control of ramipril-containing drug products.