الفهرس 
GENERAL INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
According to the recent surveys of World Health Organization, cardiovascular diseases are the leading cause of mortality all over the world. Hypertension is considered the most prevalent cardiovascular disease being with nearly one billion of the world’s population suffering from high blood pressure, and it is the cause of four million deaths per year.
In an attempt to improve the clinical outcome and achieve the targeted blood pressure reduction of antihypertensive drugs different, conventional approaches were adopted to improve their bioavailability and efficacy such as using surfactants, salt formation, inclusion complexes with cyclodextrins and synthesis of prodrugs. However, those interventions were insufficient in some cases and failed to achieve their purposes.
Recently, various nanotechnology based drug delivery systems such as lipid based drug delivery systems, vesicular systems, polymeric nanopartilces, dendrimers and nanocrystals proved to be promising technologies for improving the efficacy of cardiovascular drugs.
<The introductory part of the thesis includes a literature survey on the use of nano drug delivery systems for some cardiovascular drugs and focus on the application of solid dispersion as tool for in situ formation of nanocrystals.
The work in the thesis endeavors to improve the efficacy of candesartan cilexetil as a problematic potent cardiovascular drug. It is divided into two main parts:
<Part one: In-vitro assessment of the quality of some candesartan cilexetil raw materials and commercial tablets marketed in Egypt
This part assessed the effect of candesartan cilexetil raw materials quality on the dissolution rate as it is considered the rate limiting step for the absorption of BCS class-II drugs.
In addition to evaluation of the dissolution profile of some Egyptian market generic products in comparison to the reference brand product Atacand®.
Factors such as solubility, particle size distribution and crystal habit were studied and related to the dissolution behavior of unprocessed powder using the pharmacopeial dissolution testing conditions of candesartan cilexetil 32 mg tablet.
The results proved the effect of raw material physical properties on the pharmaceutical quality and dissolution release profile of candesartan cilexetil, where powder aggregation had a suppressing effect on the dissolution rate.
However, process of formulation can overcome those drawbacks of the raw materials.