الفهرس 
Chapter I: IntroductionOnly 14 pages are availabe for public view
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Abstract
The present thesis describes preparation and investigation of the performance characteristics of new plastic membrane and carbon paste selective electrodes of the conventional polymer membrane types for the pharmaceutical compound: terazosin hydrochloride (Teraz HCL). The active entity is a plasticized poly vinyl chloride (PVC) membrane containing a dissolved ion-exchanger which is phosphotungestic or tetraphenylborate and reineckate salts of terazosin. The thesis comprises four chapters:
Chapter (1)
It includes an introduction concerning the theoretical bases of the pharmaceutical analysis for quality control and the research studies, emf response of membrane electrodes, general properties and the different types of ion-selective electrodes.
Chapter (2)
This chapter comprises the literature survey on the different methods used for the determination of terazosin hydrochloride.These include chromatographic, spectrophotometric, voltammetric and capillary zone- electrophoresis methods. from this literature survey, it was obvious that no ion-selective electrodes for determination of terazosin have been prepared.
Chapter (3)
It describes the experimental part of the thesis dealing with materials, reagents and instruments used as well as the experimental techniques applied. Full details are given concerning preparation of Teraz-PT, Teraz-TPB and Teraz-reineckate electrodes of the conventional polymer membrane and carbon paste types. Construction of the calibration graphs and investigation of the effect of soaking, pH, and temperature on the performance characteristics of the concerned electrodes.Methods of evaluation of the electrode selectivities of the formed ion-associates and determination of terazosin hydrochloride in pure solution and in their pharmaceutical formulation are also described.
Chapter (4)
This chapter deals with the results and discussion, which may be summarized as follows:
Two conventional PVC membranes and three chemically modified carbon paste electrodes have been prepared, fully characterized and used in this study. The conventional PVC membrane electrodes are based on the incorporation of the ion-associte in PVC matrix using DPB as a plasticizer.The base of chemically modified carbon paste electrodes is a mixture of powdered graphit, plasticizer and ion- associte.
The performance characteristics and uses of these electrodes were fully discussed in terms of:-
1- The usable concentration ranges of the electrodes which are wide enough in most of the case to measure as low as 3.98 x 10-5 - 1x 10-2M.
2- The effect of soaking on life span of the electrodes.
3- Optimization of the electrodes response in FIA conditions.
4- The effect of pH changes on the electrodes performance. The potential variations due to pH changes are considered acceptable in the pH 2.0 - 6.8 for Teraz-TPB plastic membrane, 2.0 - 6.9 for Teraz-TPB carbon paste, 2.0 - 6.7 for Teraz-reineckate and the ranges 2.0 - 6.9 for Teraz-PTA, respectively.
5- The study of the effect of temperature change on the response of Teraz-PT, Teraz-TPB and Teraz-reineckate electrodes showed that they are thermally stable up to 70 oC, exhibiting temperature coefficients of 1.76 x 10-3, 1.66 x 10-3 and 1.15 x 10-3 V/ oC, respectively. In case of Teraz-TPB and Teraz-reineckate plastic membrane electrodes showed that they are thermally stable up to 70oC, exhibiting isothermal temperature coefficients of 1.10 x 10-3 and 1.20 x 10-3 V/ o C, respectively.
6- The selectivity of electrodes towards different substance and ionic species was checked both in batch and FIA conditions and the values of selectivity coefficients were calculated to evaluate their degree of interferences. The obtained values indicate that the present electrodes have high ability to discriminate between the tested drug cation and interfering substances.
7- Analytical applications involve determination of the studied drug and pharmaceutical preparations using standard additions method, potentiometric titration, flow injection technique and determination of terazosin hydrochloride in spiked urine samples.
8- Statistical treatment of the results obtained from the analytical applications using F-test and t- test treatments reflects the accuracy of this method.
The thesis ends with a list of references, which were of great help to the authoress.