A high-performance liquid chromatographic procedure is presented for the determination of hydrochlorothiazide (HCT) and enalapril maleate (EM) in pharmaceutical tablets. An aliquot of the sample is dissolved in 15% acetonitrile (ACN) containing thiophylline as an internal standard and chromatographed on a Supelcosil LC-8 (5 \mu m), (150 mm x 4.6 mm i.d.) column. The mobile phase was 3.0 mM tetrabutylammoniumhydrogen sulfate (TBAHS) in ACN/water/triethylamine (TEA), (14, 85.6, 6.4 V/V) adjusted to pH 4.1 by glacial acetic acid. The detection was at 220 nm. The method was tested for linearity, accuracy, recovery, and specificity.
AL-MOMANİ, IDREES F. (2001) "Determination of Hydrochlorothiazide and Enalapril Maleate in Tablet Formulations by Reversed-Phase HPLC," Turkish Journal of Chemistry: Vol. 25: No. 1, Article 6. Available at: https://journals.tubitak.gov.tr/chem/vol25/iss1/6