ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Development and greenness assessment of a potentiometric sensor for the determination of diuretic drug indapamide in pharmaceutical samples

Isa Mert Eski, Oguz Özbek, Onur Cem Altunoluk, Tarık Balkan, and Ömer Isildak

Department of Molecular Biology and Genetics, Faculty of Science and Arts, Tokat Gaziosmanpaşa University, Tokat, Turkey

E-mail: oguz.ozbek@gop.edu.tr

Received: 12 April 2026  Accepted: 30 April 2026

Abstract:

Diuretics are defined as substances that increase urine flow and water excretion, and they are among the most frequently prescribed medications. Indapamide (Ind) is a thiazide-like diuretic drug commonly used as an antihypertensive. Despite its clinical use, indapamide consumption should be limited to a dose of 2.5 mg per day. In this study, a potentiometric sensor was developed for the rapid, reliable, simple, selective, and low–cost determination of indapamide. Firstly, the indapamide–tetraphenylborate ion pair (Ind–TPB) was synthesized. Subsequently, polymeric membrane sensors were fabricated by incorporating the synthesized ion pair as the ionophore. The developed sensor had a wide linear working range of 1.0 × 10^− 2–1.0 × 10^− 5 M, and a detection limit of 4.69 × 10^− 6 M. The developed sensor showed a rapid response time of 15 s, along with a broad operational pH range (6.0–10.0) and a temperature range of 25–40 °C. The greenness of the proposed sensor was evaluated using the AGREE (Analytical Greenness) and the GAPI (Green Analytical Procedure Index) metrics. The accuracy of the developed sensor was assessed by comparison with a reference liquid chromatography-tandem mass spectrometry (LC–MS/MS) method, and good agreement was observed between the two methods. These results confirm that the proposed sensor provides accurate and reliable determination of indapamide in pharmaceutical formulations.

Keywords: Indapamide; Diuretics; Ion–pair; Potentiometry; PVC membrane electrode; Green analytical chemistry; Pharmaceutical analysis

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-04994-0

Chemical Papers 80 (9) 10105–10114 (2026)