استفاده از مايعات يوني، نانو لوله هاي كربني و حد واسط كتكولي در تهيه حسگرهاي الكتروشيميايي جهت آناليز داروهاي ايزوپروترنول، متيل دوپا و بنزرازيد با استفاده از روش هاي ولتامتري

چكيده انگليسي :

Application of Ionic Liquid Multiwall Carbon Nanotubes and Catechol Mediator to Preparate Electrochemical Sensors for Analysis of Isoproterenol Benserazide and Methyldopa by Voltammetric Methods Hajar Bahrami Hajar bahrami@yahoo com January 31 2012 Department of Chemistry Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiAli A Ensafi Email Ensafi@cc iut ac irAbstract In the first section of this project the oxidation of isoproterenol ISPT has been studied at amodified carbon nanotubes paste electrode using electrocatalytic effect of N 3 4 dihydroxyphenethyl 3 5 dinitrobenzamide DHPB Isoproterenol is known as catecholamines which are the importantneurotransmitters and being used for the treatment of neural disorders such as Heart disease Theelectrochemical behavior of the isoproterenol at this modified electrode was studied by cyclic voltammetry square wave voltammetry chronoamperometry and electrochemical impedance spectroscopy The modifiedelectrode showed very efficient electrocatalytic activity for the anodic oxidation of isoproterenol owing todecrease in anodic overpotentials The results indicated that in the presence of isoproterenol the anodic peakcurrent of the mediator enhanced Thus the measurement of isoproterenol with DHPB is based upon thiscurrent enhanced that is proportional with isoproterenol concentration Some of apparatus and cocentrationparameters at pH 7 for the determination of isoproterenol were optimized The kinetic parameters such aselectron transfer coefficient diffusion coefficient and catalytic reaction rate constant were also determined Under the optimum conditions ISPT was measured in the range of 0 3 to 125 0 M with a detection limit of0 1 M The relative standard deviation RSD for seven successive determination of 1 0 and 20 0 MISPT were 1 9 and 1 2 respectively The influence of various substances as potentially interferingcompounds with the determination of ISPT was studied under the optimum conditions In order todemonstrate the ability of the modified electrode to the determination of ISPA in real samples determinationof ISPA in injection solution serum water and urine samples were examined In the second section application of 1 hexyl 3 methylimidazolium hexafluorophosphate as an ionicliquide for modification of carbon paste electrode in the presence of TiO2 nanoparticles was studied fordetermination of benserazide and methyldopa Benserazide D L serine 2 2 3 4 trihydroxyphenyl methyl hydrazide used with levodopa for treatment of Parkinson s disease Benserazide isan irreversible inhibitor of peripheral L aromatic amino acid decarboxylase Methyldopa methyl 3 4 dihydroxyphenylalanine is a catecholamine widely used to treat high blood pressure Cyclicvoltammetry square wave voltammetry chronoamperometry and electrochemical impedance spectroscopywere used as diagnostics and measurement techniques Some of effective parameter in fabrication of thesensor such as percentage of ionic liquide and TiO2 nanoparticles were optimized The results showed thatthe maximum sensitivity was obtained with 10 0 w w TiO2 and 15 0 w w IL Under the optimizedconditions the calibration curves were linear in the concentration range of 1 0 to 600 0 M benserazide witha limit of detection of 0 2 M and 0 5 to 345 0 M methyldopa with a limit of detection of 0 2 M Therelative standard deviation for 10 0 M benserazide and methyldopa were 1 4 and 1 6 respectively Inorder to investigate the influence of various species on the determination of benserazide a fixed amount ofbenserazide and methyldopa 5 M was taken with different amounts of foreign species and analyzed withcyclic voltammetry The results demonstrate the modified electrode has a good selectivity for benserazideand methyldopa The proposed sensor was successfully used for determination of benserazide and methyldopain human urine and pharmaceutical product tablet Keywords Carbon nanotubes paste electrode TiO2 nanoparticles Ionic liquide Isoprote

بهرامي، هاجر

الكترودهاي خمير كربن , نانوذرات تيتانيوم اكسايد , 3و5- دي نيتروبنزاميد