الفهرس 
PART IOnly 14 pages are availabe for public view
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Abstract
The thesis deals with the analysis of some selected drugs used in the treatment and management of cardiovascular disorders mainly hypertension. The selected drugs belong to several pharmacological groups such as the β-blockers, diuretics, calcium channel blockers and angiotensin II receptor antagonists. The thesis comprises four parts:
Part I
This part contains a general introduction about the chemical names, structures, physical properties, pharmacological actions and uses of the studied drugs. It also contains literature reviews for the pharmacopoeial and other reported methods of analysis for the selected drugs in pharmaceutical dosage forms as well as in biological fluids.
Part II
This part describes two spectrophotometric methods for analysis of losartan potassium as well as the binary mixture of losartan potassium and hydrochlorothiazide. This part includes two chapters.
Chapter 1:
This chapter deals with the development of a spectrophotometric method for analysis of losartan potassium based on the oxidation reaction with cerium (IV) sulphate in presence of sulphuric acid at 90 ºC followed by measurement of the decrease in absorption at 318 nm. The different experimental parameters were carefully studied and optimized with respect to volume of cerium (IV) solution, molarity of sulphuric acid solution, reaction temperature and time. Regression analysis for the calibration curve showed good linear relationship between absorption and losartan concentration over the range of 10 - 50 µg/mL. The stoichiometry of the reaction was investigated and the reaction pathway was postulated. The proposed method was applied for determination of losartan potassium tablet dosage forms either single or in combination with hydrochlorothiazide.
Chapter 2:
It describes the determination of the binary mixture of losartan potassium and hydrochlorothiazide using the recently published ratio difference spectrophotometric method. Losartan was determined using 50 µg/mL hydrochlorothiazide as divisor to generate the ratio spectra and the difference between the ratio amplitudes at 242 and 275 nm was measured. Similarly, hydrochlorothiazide was determined using 50 µg/mL losartan as divisor then the difference between the ratio amplitudes at 275 and 224 nm was recorded.
Calibration curves were linear in the concentration ranges 5 - 60 and 5 - 50 µg/mL for losartan potassium and hydrochlorothiazide, respectively. The described method was applied for simultaneous determination of losartan potassium and hydrochlorothiazide in their combined tablet dosage forms.