الفهرس 
Part I: IntroductionOnly 14 pages are availabe for public view
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Abstract
The presented thesis concerned with analytical study of some hypoglycemic drugs in pharmaceutical formulations and biological fluids. These drugs are Dapagliflozin (DGF), Empagliflozin (EGF) And Saxagliptin (SXG). The presented thesis falls into three parts:
Part I: Introduction
This part provides a general introduction about the investigated drugs such a pharmaceutical importance’s, chemical structures and analytical reviews for the studied drugs. At the end of this part, the objective of the suggested work was described.
Part II: chromatographic Methods
This part divided into two chapters; as follows:
Chapter 1: This chapter deals with a proposed high performance thin layer chromatographic analytical method (HPTLC) for simultaneous determination of DGF and SXG. The method was proved to be simple, fast and sensitive. It was depend on separating these compounds using hexane: ethyl acetate: methanol in a ratio of 4: 4: 2 as a mobile phase. Silica 60 F254 was used as a stationary phase. Scanning was performed at a wavelength of 225 and 210 nm, for DGF and SXG; respectively. Stability of these compounds has been studied after exposure to various stress conditions. The studied drugs have been subjected to acidic hydrolysis, basic hydrolysis, oxidizing agents and photolysis. The proposed method was proved to be selective for the examined drugs, as they were analyzed in the presence of their degradation products. All variables that affect this method were studied. The obtained results were linear over (50-550) ng/band. This method was applied successfully to analyze these compounds in their pharmaceutical preparations without any interference from excipients. The results have been successfully compared with the reported HPTLC methods and this study can be relied upon to study the stability of these drugs.
Chapter 2: This Chapter described simple, selective and sensitive HPTLC method for analysis of DGF. The used detector was fluorescence detector. The excitation wavelength was 278 nm. The used mobile phase was hexane: ethyl acetate: methanol in a ratio of 4: 4: 2. Silica 60 F 254 was used as a stationary phase. All variables that affect this method were studied. The obtained data were linear over (30-400) ng/band. The proposed method was proved to be selective, as it was able to analyze DGF in real plasma and urine samples without interferences from sample matrices. The method was applied successfully to analyze DGF in its tablets and biological fluids without any interference from neither pharmaceutical excipients nor biological samples matrices. The results have been successfully compared with the reported HPTLC methods and this method could be applied to pharmacokinetic study of DGF.
Part III: Electrochemical method
Chapter 1: This Chapter deals with a design of highly sensitive electrochemical analytical method for the assay of DGF in its tablets and biological samples. A new sensitive electrode consisting of PDAN has been polymerized on the surface of GCE. The effect of polymer on the electrode surface has been examined as supporting materials on the catalytic oxidative activity of the deposited nanoparticles on the electrode surface for DGF oxidation. Electrochemical examination showed that (Pt/PDAN/GCE) was excellent for oxidation catalytic activity for DGF oxidation. Physico-chemical characterization of the prepared nanostructures was performed by electron scanning, atomic force microscope and voltametric methods. Therefore, this nanocatalyst electrode has demonstrated attractive specific amplitude and long life span, which could be used in various applications.
Part Ⅳ: Spectrofluorimetric Methods
This part divided into three chapters; as follows:
Chapter 1: This Chapter presented a sensitive and selective spectrofluorimetric method for DGF analysis in its pure form and in biological fluids. This method based on the interaction of the hydroxyl group present in DGF with benzofurazan derivative to give a yellow color. The produced color was measured at 453 and 522 nm for excitation and emission wavelengths; respectively. Different conditions which affect the reaction was tested by using factorial design experiments. The relationship was linear over a range of (50-1000) ng/mL of DGF. The percentage recovery was 99.84% with a standard deviation of ± 1.34. The limit of detection was 14.24 ng/ mL and a limit of quantitation was 43.14 ng/mL for DGF. The proposed method has been applied to DGF’s commercially available tablets and in human plasma samples. Therefore, the proposed study proved to be suitable for investigating DGF in clinical research and quality control facilities.
Chapter 2: This Chapter presented a sensitive and selective spectrofluorimetric method for EGF assay in its pure forms and in biological fluids. This method based on the interaction of hydroxyl group present in EGF with benzofurazan derivative to give a yellow color. The produced color was measured at 455 and 521 nm for excitation and emission wavelengths; respectively. Different conditions, which affect the reaction was studied. The relationship was linear over a range of (50-1000) ng/mL of EGF. The percentage recovery was 99.92% with a standard deviation of ± 0.68. Limit of detection was 15.55 ng/ mL and a limit of quantitation was 46.63 ng/mL for EGF. The proposed method has been successively applied to its commercially available tablets and human plasma samples. Therefore, the proposed study was able to investigate EGF in its clinical studies and quality control facilities.
Chapter 3: This chapter included the development of three methods of spectral analysis for the identification of DGF. The first method depended on the intensity of the self-description of this drug, and it was very simple, fast and highly sensitive method for quantifying DGF in methanol at the emission of 307 nm after excitation at 278 nm. The second and third method relies on persistence in the presence of derivatives to check its stability under different conditions. The second derivative spectrum was measured to determine DGF in its pure form and commercially available pharmaceutical forms and in the presence of degradation products. DGF has been subjected to acidic hydrolysis, basic hydrolysis, oxidizing agents and photolysis. The results showed that, DGF could be assayed without any interference at the zero crossing points at 318 and 322 nm, for both first and second derivatives, respectively. The relationship was linear over a range of (0.1-1.0) µg/mL. Therefore, the proposed method can be used in a quality control of DGF commercial products. The obtained results confirmed that the proposed method was considered as stability indicating assay for DGF.