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, ...

1-(2-Pyridylazo)-2-naphthol (PAN) has been used for the simultaneous and individual determination of palladium and cobalt at trace levels. PAN complexes of palladium and cobalt at neutral pH form green-color neutral complexes, which are soluble in aqueous SDS micellar media. Under optimum conditions, calibration graphs for individual determinations by zero and first-derivative spectrophotometry...

Two methods, spectrophotometric and chromatographic-densitometric ones, were developed for determination of losartan potassium, quinapril hydrochloride and hydrochlorothiazide in pharmaceutical preparations. Spectrophotometric method involved derivative spectrophotometry and zero order spectrophotometry. The measurements were carried out at lambda = 224.0 nm for quinapril, lambda = 261.0 nm for...

The use of derivative UV-spectrophotometry is proposed for the simultaneous quantification of promazine hydrochloride in the presence of sulfoxide, and vice versa. For this purpose, mathematical parameters were established for generating derivative spectra of analytes. The determination of promazine was made using the first-order derivative (deltalambda = 10 nm, second polynomial degree) at 268...