Hydroflumethiazide

A stability indicating RP-HPLC method was developed for the simultaneous determination of Spironolactone (SRL) and Hydroflumethiazide (HFM) in pharmaceutical dosage form. Inertsil ODS - C18 (250 mm x 4.6 mm, 5 µm) column and mobile phase of methanol: acetonitrile : phosphate buffer in the ratio of 55:40:05 v/v at a flow rate of 1.0 mL/min was used for separation of the components. The components were detected at a wavelength of 221nm using UV detector. The Spironolactone and Hydroflumethiazide were separated at retention time 4.67 and 6.74 min respectively. The developed method was validated in terms of precision, accuracy, linearity, specificity, limit of detection, limit of quantitation. The range of linearity was found to be 5-30 µg/mL for Hydroflumethiazide and 5-30 µg/mL for Spironolactone. The proposed method was applied to study the stability of the drugs under different degradation conditions such as acid, alkali, peroxide, thermal and photo light. The developed method was found to be simple, sensitive and rapid and hence, It can be adopted in any laboratory for quality control analysis.

A simple and precise reversed-phase high performance liquid chromatography (HPLC) method for the determination of hydrochlorothiazide (HCT) in human plasma was developed and validated. Using hydroflumethiazide as an internal standard (IS), separation was achieved on Atlantis dC 18 column. The mobile phase, 10 mM monobasic potassium phosphate and acetonitrile (80:20, v: v), was delivered at a flow rate of 1.2 ml/min. The eluent was monitored by photodiode array detector, with the wavelength set at 272 nm. Plasma samples containing HCT and IS were extracted with methyl tert butyl ether and reconstituted in mobile phase. No interference in blank plasma or of commonly used drugs was observed. The relationship between the concentration of HCT in plasma and peak area ratio of HCT to the IS was linear over the range of 5-300 ng/ml. The intra-day and inter inter-day coefficient of variation and bias were