الفهرس يوجد فقط 14 صفحة متاحة للعرض العام
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المستخلص
This thesis is concerned with the spectrophotometric analysis of some antiulcer drugs (H2-antagonists) namely; cimetidine, famotidine, nizatidine, and ranitidine hydrochloride. Depending on the properties of these drugs, different spectrophotometric methods were developed. The thesis comprises five chapters in addition to an introduction about the studied drugs and the different official and reported methods described for their analysis.
Thesis includes the following chapters:
Chapter I: This chapter includes a simple and specific spectrophotometric method, which is developed for the determination of the studied drugs by reaction with chloranil.
Chapter II: This chapter involves the development and validation of three simple and sensitive spectrophotometric methods for determination of nizatidine and ranitidine in their pharmaceutical dosage forms. These methods were based on the interaction between the N-alkylvinylamine formed from the interaction of the free secondary amino group in the investigated drugs with acetaldehyde and each of chloranil, bromanil, and 2,3-dichloronaphthoquinone.
Chapter III: In this chapter the studied drugs were analyzed by three simple, accurate and sensitive spectrophotometric methods. The methods depend on the oxidation of the studied drugs with excess N-bromosuccinimide (NBS), followed by measuring the excess unreacted NBS at different time intervals either by formation of a pink chromogenic product with fluorescien that showed lmax at 518 nm or a violet chromogenic product with p-amino phenol that showed lmax at 552 nm, or by decreasing of a blue color of indigo carmine dye that showed lmax at 607 nm.
Chapter IV: In this chapter, two simple, accurate and sensitive spectrophotometric methods for analysis of the investigated drugs have been developed and validated. The methods were based on the oxidation of these drugs with cerium (IV) in presence of perchloric acid and subsequent measurement the excess Ce(IV) by its reaction with each of p-dimethylaminobenzaldehyde and p-dimethylaminocinnamaldehyde to give red colored products (lmax at 464 nm).
Chapter V: This chapter involves the direct oxidation of the studied drugs with potassium permanganate solution in presence of sulphuric acid. The concentrations of the drugs in their samples were determined by measuring the decrease in the absorption intensity of the colored permanganate at 525 nm.