الفهرس 
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Abstract
The thesis deals with the fabrication of new ion selective electrodes on the basis of chemically modified all-solid contact electrodes, with coated graphite or coated gold wire substrates. The investigation of their characteristic performance and evaluation of their industrial and environmental matrices applications have been extensively considered. The thesis contains seven chapters.
Chapter one deals with an introduction that is performing a precise literature survey focusing on the electro-chemical sensors covering the last two decades. The characterization of ion selective electrodes, and their application in pharmaceutical, industrial and environmental matrices have been thoroughly surveyed.
Chapter two is describing the experimental part which contains reagents and materials, apparatus, methods, and so on.
Chapter three reports the preparation of a novel lipoate-selective membrane sensor for the flow injection determination of α-lipoic acid in an industrial pharmaceutical preparations and urine
Abstract: A potentiometric lipoate-selective sensor based on mercuric lipoate ion-pair as a membrane carrier is reported. The electrode was prepared by coating the membrane solution containing PVC, plasticizer, and carrier on the surface of graphite electrode. Influences of the membrane composition, pH, and possible interfering anions were investigated on the response properties of the electrode. The sensor exhibits significantly enhanced response toward lipoate ions over the concentration range 1x10-7 mol L-1 to 1x10-2 mol L-1 with a lower detection limit of (LDL) of 9 x 10-8 mol L-1 and a slope of −29.4 mV decade−1, with SD of the slope is 0.214 mV. Fast and stable response, good reproducibility, long-term stability, applicability over a pH range of 8.0–9.5 is demonstrated. The sensor has a response time of ≤12 s and can be used for at least 6 weeks without any considerable divergence in its potential response. The proposed electrode shows good discrimination of lipoate from several inorganic and organic anions. The CGE was used in flow injection potentiometry (FIP) and resulted in well defined peaks for lipoate ions with stable baseline, excellent reproducibility and reasonable sampling rate of 30 injections per hour. The proposed sensor has been applied for the direct and FI potentiometric determination of LA in pharmaceutical preparations and urine; and has been also utilized as an indicator electrode for the potentiometric titration of LA.
Chapter four reports the preparation of a durable solid-contact perchlorate sensor with nanomolar detection limit based on covalently attached cobalt phthalocyanine ionophores
Abstract: A durable solid-contact perchlorate sensors based on cobalt phthalocyanine-C-monocarboxylic acid (I), and cobalt phthalocyanine-C,C,C,C-tetracarboxylic acid (II) as free ionophores and covalently attached to polyacrylamide (PAA)—ionophores III and IV, respectively were prepared. The all solid-state sensors were constructed by the application of a thin film of a polymer cocktail containing a phthalocyanine ionophore and cetyltrimethylammonium bromide (CTMAB) as a lipophilic cationic additive onto a gold electrode precoated with the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 10.3% of ionophore (III) covalently attached to plasticizer-free poly(butyl methacrylate-co-dodecyl methacrylate) (PBDA) exhibited a good selectivity for perchlorate and discriminated many ions, including F-, Cl-, Br-, I-, SCN-, NO3-, S2- and SO42-. The covalent attachment of the ionophore to the polymer resulted in a near-Nernstian anionic slope of -62.3 mV/ decade whereas a super-Nernstian slope of -79.9 mV/ decade was obtained for the free ionophore. The sensor covered a linear concentration range of 5×10-9–1×10-2 mol L-1 with a lower detection limit (LDL) of 1×10-9 mol L-1 and gave a stable response over a pH range of 4–10.5. The all-solid state sensors were utilized for the selective flow injection potentiometric determination of perchlorate in natural water and human urine samples in the nanomolar concentration range.
Chapter five considers the construction of a durable solid contact Sensor for the selective FIP determination of sulfide ion in environmental samples
Abstract: A durable sulfide-selective solid-contact sensor based on cerric complex of ABPAH [N’-Acetyl-2-(benzothiazol-2yl)-3-(3-chloro-5-metyl-4H-pyrazol-4-yl) acrylohydrazide] covalently attached to polyacrylamide (PAA) as ionophore has been developed and potentiometrically evaluated. The all solid-contact sensor was constructed by the application of a thin film of a polymer cocktail containing the ABPAH-PAA ionophore and plasticizer free– PBDA copolymer (Butylmetha acrylate – dodecyl metha acrylate) onto a gold electrode pre-coated with the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor containing 12.5% of the ABPAH-PAA ionophore showed a Nernstian slope of -29.42 mV/ conc. decade with linear range of 1.0X10-8 - 1.0X10-2 mol L-1and detection limit of 2.0X10-9mol L-1. The potentiometric response of the sulfide selective electrode was found to be independent on the pH of solution at pH 13. The proposed sulfide sensor has been utilized as a detector for the flow injection potentiometric determination of sulfide ion in sewage, marsh and industrial waste water using sulfide anti-oxidant buffer (SAOB) as a carrier solution.
Chapter six reports the preparation of solid contact monohydrogenphosphate-selective electrode based on copper - monoaminophthalocyanine covalently attached to acrylate polymer
Abstract: Novel solid-contact monohydrogen phosphate sensor based on mono-amino copper-phthalocyanine covalently attached to acrylate polymer. The all solid-contact sensors were constracted by the application of a thin film of a polymer cocktail containing a phthalocyanine ionophore and Benzyl dimethyl hexadecyl ammonium chloride (BDMHAC) as a lipophilic cationic additive onto a gold electrode pre-coated with the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) as an ion and electron transducer. The sensor with 12.5% of ionophore covalently attached to plasticizer-free poly(butyl methacrylate-co-dodecyl methacrylate) (PBDA) exhibited a good selectivity for dibasic phosphate and discriminated many ions, including F-, Cl-, Br-, I-, AcO-, NO3-, ClO4-and SO42-. The covalent attachment of the ionophore to the polymer resulted in a Nernstian anionic slope of -29.85 mV/ decade. The sensor covered a linear concentration range of 4×10-9–1×10-2 mol L-1 with a lower detection limit (LDL) of 1×10-9 mol L-1. The all-solid contact sensors were utilized for the selective flow injection potentiometric determination of dibasic phosphate in natural water samples in the nanomolar concentration range.
Chapter seven considers the construction of potentiometric electronic tongue to resolve mixtures of sulfide and perchlorate anions