Simultaneous Determination of Cyproterone Acetate and Ethinylestradiol in Tablets by Derivative Spectrophotometry

Simultaneous Determination of Losartan and Hydrochlorothiazide in Pharmaceutical Preparations by Derivative and Ratio Derivative Spectrophotometry

Background & Aims: Losartan is a non-peptide potent antihypertensive agent that acts through blocking angiotensin II receptors. Hyzaar® is a combination product that contains two drugs, losartan and hydrochlorothiazide, used to lower high blood pressure. There are some reports regarding simultaneous measurement of the drugs in pharmaceutical and biological samples which includes HPLC, CE, CEC, ...

Simultaneous determination of dextromethorphan HBr and bromhexine HCl in tablets by first-derivative spectrophotometry.

A rapid, simple and direct assay procedure based on first-derivative spectrophotometry, using a zero-crossing and peak-to-base measurement at 234 and 324 nm, respectively, has been developed for the specific determination of dextromethorphan HBr and bromhexine HCl in tablets. Calibration graphs were linear with the correlation coefficients of 0.9999 for both analytes. The limit of detections we...

Determination of citalopram in tablets by capillary zone electrophoresis and by direct and derivative UV-spectrophotometry.

Three rapid, simple and accurate analytical methods for the determination of citalopram in tablets were developed. The capillary zone electrophoresis (CZE) method was carried out using fused silica capillary with 67 mM phosphate buffer pH 7.0 as the background electrolyte, 30 kV of separation voltage and UV detection at 239 nm. The direct spectrophotometric method was performed by measuring the...

Simultaneous Quantitation of Theophylline and Guaifenesin in Syrup by HPLC, Derivative and Derivative Ratio Spectrophotometry for Quality Control Purposes

The aim of the present work was to develop a simple and rapid method for determination of theophylline (THP) and guaifenesin (GU) in syrup without involving any preparation operations like separation or masking. A HPLC and two spectrophotometric methods based on the derivation of the main spectra are described for the determination of THP and GU in combined pharmaceutical syrup form. The first ...

simultaneous determination of timolol maleate and latanoprost tartrate in ophthalmic preparations by derivative spectrophotometry