TITLE:
Comprehensive Evaluation and Stability Indication of HPLC-UV and HPLC-Fl Methods for the Synchronic Analysis of Three Antihypertension Agents Hydrochlorothiazide, Amlodipine, and Valsartan
AUTHORS:
Khalid Hamad Abu-Shandi
KEYWORDS:
Hydrochlorothiazide, Amlodipine, Valsartan, Combination, Drug Analysis
JOURNAL NAME:
Journal of Biosciences and Medicines,
Vol.13 No.10,
October
20,
2025
ABSTRACT: Simultaneous determination of hydrochlorothiazide (HCT), amlodipine (Am), and valsartan (Val) drugs is performed. A high-performance liquid chromatography (HPLC) method with UV detection is used at 315 nm for the determination of hydrochlorothiazide, 357 nm for amlodipine, and 245 nm for valsartan. The method is applied in solution and pharmaceutical formulations. The method was extended to detect the three drugs by HPLC with a fluorescence detector at (λex = 315/λem = 321 nm for hydrochlorothiazide, λex = 357/λem = 365 nm for amlodipine, and λex = 245/λem = 247 nm for valsartan). The HPLC/UV and HPLC/Fl methods were found to be precise, accurate, and sensitive. Gradient separation was employed on a C18 column (250 × 4.6 mm i.d., 5 µm) at room temperature. A water/acetonitrile/glacial acetic acid mixture (300:700:1 by volume) was used as the mobile phase. The drugs under investigation were found to have 93% - 101% recovery from solution and pharmaceutical formulations. The calibration curve was linear over the range of 0.010 - 10.0 µg/mL for hydrochlorothiazide, amlodipine, and valsartan. The limits of quantification (LOQ) were: (0.020 µg/mL) for hydrochlorothiazide, (0.030 µg/mL) for amlodipine, and (0.030 µg/mL) for valsartan. The limits of detection (LOD) were: 0.010, 0.020 µg/mL, and 0.020 µg/mL for hydrochlorothiazide, amlodipine, and valsartan, respectively.Graphical Abstract