الفهرس 
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Abstract
The present thesis describes the preparation and investigation of performance characteristics of ion-selective electrodes for Alverine citrate. The electrodes are of polymeric membrane, coated wire and modified carbon paste types. The active recognition in the proposed electrodes is liquid ion exchange mechanism depending upon ion-exchanger which is ion-associate of the Alverine cation with phosphotungstate, phosphomolybdate, reineckate and tetraphenyl- borate anions incorporated in the polymeric membrane or carbon paste.
Chapter 1: Presents the theoretical basis of the general properties of the different types of ion-selective electrodes, selectivity, potential applicability and applications of ion-selective electrodes in pharmaceutical analysis.
Chapter 2: Discuss the construction and performance characteristics of novel alverine citrate plastic membrane electrodes based on incorporation of alverine citrate with the ion exchangers, sodium tetraphenylborate (Alv-TPB), ammonium reineckate (Alv-Rt) and a mixture of both (Alv-TPB/Rt) into plasticized poly(vinyl chloride) membrane. The sensors showed a near-Nernstian slope of 57.2, 56.3 and 57.1 mV decade-1 at 25±0.1°C within the concentration range 1.0×10-5-1.0×10-2, 1.9 ×10-5-1.0×10-2 and 3.9×10-5-1.0×10-2 mol L-1 Alverine citrate, with detection limits of 4.1×10-6, 3.9×10-6, 9.3× 10-6 mol L-1 Alverine citrate for Alv-TPB, Alv-Rt, Alv-TPB/Rt electrodes, respectively. The membrane electrodes performed satisfactorily over the pH ranges of 1.4-7.5, 1.5-7.9 and 1.5-7.8 for the three electrodes, respectively. The selectivity coefficients of the developed sensors indicated excellent selectivity for Alverine cation. Surface analysis using scanning electron microscopy was used to determine the cause of the limited life span of plastic membrane electrode. The proposed sensors displayed useful analytical characteristics for the determination of Alverine citrate in pharmaceutical preparation and biological fluids such as plasma and urine samples.
Chapter 3: Describes the selective alverine electrodes which have been fabricated by constructing a polymeric membrane (PME) and coated wire (CWE) electrodes.
These are based on the ion-pair between phosphotungstic acid (PME1, CWE1) and phosphomolybdic acid (PME2, CWE2) in a poly (vinyl chloride) matrix, plasticized with DBP. The influence of membrane composition and pH on the potentiometric responses of electrodes was investigated. The response characteristics of the membrane were compared with polymeric membrane electrode (PME) as well as with coated wire electrode (CWE). The electrodes exhibit Nernstian slope of 59.1±0.4, 59.3±0.6, 59.2±1.1 and 59.5±1.1 mV decade-1 with limits of detection of 7.6×10-6, 8.3×10-6, 6.6×10-6 and 8.1×10-6 mol L-1 alverine citrate for PME1, PME2, CWE1 and CWE2, respectively. Furthermore, the electrodes generated constant potentials in the pH range of 1.4-8.1 and 1.4-8.3 for PME1 and PME2, respectively. selectivity coefficients for alverine citrate relative to numbers of potential interfering substances were investigated. The electrodes were highly selective for alverine over a number of common inorganic and organic species. The proposed electrodes displayed useful analytical characteristics for the determination of alverine citrate in bulk powder, pharmaceutical formulation, and biological fluids (urine and plasma). The practical utility of the proposed electrodes has also been demonstrated by thier usage as indicator electrodes in potentiometric titration of alverine cation with phosphotungstic acid solution.
Chapter 4: Details about New carbon paste electrodes as potentiometric sensors for alverine cation. The electrodes having alverine-tetraphenylborate (Alv-TPB), alverine-reineckate (Alv-Rt), alverine-phosphotungstate (Alv-PT) and alverine-phosphomolybdate (Alv-PM) (ion-pairs) as electroactive materials were prepared. The electrodes exhibit the following characteristics, respectively: a Nernstian slope of 59.1±0.2, 59.6±0.2, 59.3±0.3 and 59.6±0.1 mV decade-1 at 25±0.1°C with a limits of detection of 1.2×10-5, 5.3×10-6, 1.4×10-5 and 2.6×10-5 mol L-1 alverine citrate over the pH range 2.1-8.1, 1.9-7.9, 1.5-7.6 and 1.4-7.9. The electrodes have long life times with good reproducibility. The proposed electrodes revealed good selectivity for alverine with respect to a number of common inorganic and organic species. The CPEs were successfully applied for the determination of alverine cation in bulk powder, pharmaceutical formulation, and biological fluids (urine and plasma) and as indicator electrodes in potentiometric titration of alverine cation.