S-perindopril assay using a potentiometric, enantioselective membrane electrode

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Chiral Separations

Background:

• Enantiopurity is critical for pharmaceutical efficacy and safety.
• Developing selective and sensitive methods for chiral drug analysis remains a challenge.
• Potentiometric sensors offer a promising platform for rapid, cost-effective analysis.

Purpose of the Study:

• To construct and characterize a potentiometric, enantioselective membrane electrode for S-perindopril.
• To evaluate the electrode's performance for enantiopurity testing.
• To assess the electrode's selectivity and potential interferences.

Main Methods:

• Fabrication of a graphite paste membrane electrode impregnated with 2-hydroxy-3-trimethylammoniopropyl-beta-cyclodextrin.
• Application of a chronopotentiometric (zero current) technique for enantioselective potentiometry.
• Determination of enantioselectivity against R-perindopril and D-proline, and assessment of L-proline interference.

Main Results:

• The developed electrode demonstrated reliable enantiopurity testing for S-perindopril in the concentration range of 10(-5)-10(-2) mol/L.
• A low detection limit of 5 x 10(-6) mol/L and high average recovery of 99.58% (RSD = 0.33%) were achieved.
• L-proline was identified as the primary interfering compound, and the electrode surface was shown to be regenerable by polishing.

Conclusions:

• The potentiometric, enantioselective membrane electrode is a viable tool for the enantiopurity assessment of S-perindopril.
• The electrode offers good sensitivity, selectivity, and reusability, suitable for quality control applications.
• Further optimization could address L-proline interference for broader applicability.