الفهرس | Only 14 pages are availabe for public view |
Abstract The thesis comprises five chapters: Chapter I This part comprises a short account about the classification and the pharmacological action of drugs acting mainly on the gastrointestinal tract. This part mainly contains a general introduction about the chemical names, structures, physical properties, pharmacological actions and uses of the 8 drugs namely Azintamide, Chlordiazepoxide, hydrochloride, Cisapride, Drotaverine, Famotidine, Loperamide, Metoclopramide and Nifuroxazide. This chapter also introduces some reported literature reviews for the methods used for the quantitative analysis of these 8 selected drugs in their pharmaceutical preparations as well as in some biological fluids. Chapter II This chapter deals with the development and validation of 2 spectrophotometric methods for the determination of Nifuroxazide in pure form and in its tablets dosage form. The first method is based on oxidation of MBTH reagent by ceric ions in acid medium to form an electrophilic intermediate which is the active coupling species. This intermediate undergoes electrophilic substitution with Nifuroxazide to produce the oxidative coupling red product showed maximum absorption at 479 nm. The second spectrophotometric method uses Iron (III)-o-Phenanthroline reagent to oxidize Nifuroxazide and the reagent is reduced to iron II ions with the subsequent formation of an intense orange colored ferroin complex. The reaction proceeded in acetate buffer medium and the color was measured at 510 nm. The different experimental parameters affecting the development and stability of the produced colors were carefully studied and optimized for the 2 methods. The two methods were validated with respect to linearity, ranges, precision, accuracy, and limits of detection and quantification. Beer’s law was obeyed in the concentration ranges of 4-12 and 1.6-8.0 Fg/mL for method I and method II respectively with correlation coefficient values not less than 0.99948. In addition, detection limits were 0.52 and 0.18 Fg/mL for method I and method II respectively. The proposed methods were successfully applied for the assay of the drug in its capsules dosage form. Recovery data obtained by the proposed methods were favorably compared with those obtained by a reported method. Chapter III This chapter deals with the development and validation of a spectrophotometric method for the determination of Cisapride, Drotaverine and Loperamide by ternary complex formation with eosin and Pb (II). The reaction between the drug, Pb (II) and eosin is explained as ion association ternary complex of cationic binary complex with acidic dye. The reaction mixture was found to absorb quantitatively at 545 nm. |