الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
The compounds investigated throughout this work were determined in different pharmaceutical formulations and biological fluids. The studied compounds included: Phenylephrine hydrochloride, diphenhydramine hydrochloride, guaifenesin, benzonatate, memantine hydrochloride, promethazine hydrochloride, paracetamol, dextromethorphan hydrobromide, salicylamide, vitamin C, terbutaline sulfate and bromhexine hydrochloride.
At the thesis beginning there are lists of abbreviations, tables, figures and schemes cited within the thesis.
This thesis consists of five chapters:
• Chapter 1
This chapter is subdivided into five parts:
Part A
It includes a general introduction on cold and cough definition, pathogenesis and various categories of drugs used in the treatment of such conditions.
Part two
It includes a general introduction on Alzheimer̕s disease definition and treatment.
Part three
This part includes a general introduction on derivatization in HPLC and reagents used for labeling of amines and amino acids.
Part four
This part includes a general introduction on derivative spectrophotometry and derivative ratio spectrophotometry. The theory of calculations to resolve binary and ternary mixtures are discussed. The advantages and drawbacks of these methods are mentioned.
Part five
Literature review on the studied drugs determined during the study. The literature review revealed the different ways by which drugs were analyzed. In addition, their molecular structures, molecular formulae, molecular weights, physical characteristics (description - melting point - dissociation constant - the degree of solubility in various solvents) and their pharmacological effects.
• Chapter 2
This chapter contains the development of a stability indicating reversed phase high performance liquid chromatographic method for phenylephrine HCl, diphenhydamine HCl, guaifenesin and benzonatate. The drug substances were exposed to forced stress conditions of acid and alkaline hydrolysis, oxidation, photolysis and thermal degradation. Successful separation of the drugs from the degradation products formed under stress conditions was achieved on a Thermo C18 column (250 mm×4.6 mm I.D., particle size 5 µ) using dual mode gradient elution system and UV detection was carried out at 222 nm. The developed method was applied to analysis of these components in capsule and gave satisfactory results.
• Chapter 3
This chapter describes a simple, reliable and accurate RP-HPLC method using a pre-column derivatization for the determination of memantine HCl after derivatization using phenyl isothiocyanate which binds to the amine site in memantine. This coupling reaction resulted in a molecule that can be detected by UV. The chromatographic separation was achieved on a reversed-phase column [4.6 ID X 250 mm Cosmosil packed column for HPLC, 5 µm C18-MS-II code 38020-41 (Japan)]. The sample was injected with 25 µl Hamilton analytical syringe. The detection wavelength was set at 275 nm. The mobile phase was prepared by mixing (A) 10 mmol/L potassium dihydrogen phosphate, adjusted to pH 3.7±0.1 by 1 M orthophosphoric acid and (B) 100% acetonitrile, in a ratio of 50: 50. The flow rate was 1 ml/min. The derivatized product was identified by mass and IR spectra analyses. The method was applied for the determination of memantine in tablets, spiked and volunteer human plasma and urine and spiked CSF in presence of biological endogenous components. Also a urinary excretion pattern for memantine was studied. Rimantadine HCl was used as internal standard. The factors that may influence the efficiency and reproducibility of the derivatization process were identified and optimized.
• Chapter 4
In this presented chapter; simple, specific, accurate, reliable and well-defined RP-HPLC/UV methods have been established, for the first time, regarding the simultaneous determination of paracetamol, dextromethorphan HBr and promethazine HCl; (Mixture 1), and phenylephrine HCl, salicylamide, paracetamol and promethazine HCl; (Mixture 2), without any interference from the excipients. Also the five components were separated simultaneously on the same chromatogram. Validation provided that the proposed RP-HPLC methods were linear in the proposed working. Besides, being accurate, precise (repeatability and reproducibility) and specific, for separating the main drugs from all interferents within a chromatographic run not more than 20 min. The simplicity of the proposed methods allows application in ordinary laboratories that lack sophisticated analytical instruments, such as; LC/MS or GC/MS. Hence, the proposed method can be readily implemented for the routine and QC analyses.
• Chapter 5
In this chapter, new spectrophotometric methods were developed for the simultaneous analyses of vitamin C and salicylamide; (Mixture 1), and guaifenesin, terbutaline sulphate and bromhexine HCl; (Mixture 2) without prior separation. The methods were based on the use of the first order derivative spectrophotometry and first order derivative ratio spectrophotometry at zero-crossing wavelength for Mixture 1 and Mixture 2 respectively. The ratio spectra were obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentrations of the other components were then determined from their respective calibration curves treated similarly. The described methods were applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.
• References
This section provides a list of the references which have been used. These references are listed according to the order of appearance within the context of the thesis.