الفهرس 
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Abstract
Polypyrrole films doped with 2-acrylamido-2-methyl-l-propanesulfonic acid sodium salt (AMPSNa) are electrodeposited using different techniques namly chronoamperometry, chronopotentiometry, cyclic voltammetry and normal pulse voltammetry under different conditions. The prepared polypyrrole films are characterized by using infrared analysis, X- ray diffraction, scan electron microscope and cyclic voltammetry. It is found that AMPSNa doped polypyrrole films are highly crystalline with cauliflower morphology. Cyclic voltammetry studies for 0.5 M AMPSNa shows that polypyrrole - AMPSNa films prepared by chronopotentiometry, cylic voltammetry and normal pulse voltammetry are electroactive but films prepared by chronoamperometry has no significant electroactivity. Cyclic voltammetry studies for phosphate and acetate buffer solutions with different pHs shows that polypyrrole - AMPSNa films prepared by chronopotentiometry, cyclic voltammetry and normal pulse voltammetry are electroactive at pH less than 7 and at pH equal to or greater than 7, the polypyrrole films are not electroactive.
PPy-AMPSNa electrodes prepared by cyclic voltammetry, chronopotentiometry and normal pulse voltammetry are characterized by Differential pulse voltammetry technique to study its performance as biosensor for atenolol.The buffer solutions used are 1 M phosphate and acetate buffers of different pHs. In phosphate buffers, two peaks are observed. The first peak, which appeared at pH values less than 7, is propably due to the oxidation of the secondary alcoholic group of atenolol and this peak disappear at higher pH values. The second peak, which appear at pH values less than 6, is propably due to the oxidation of PPy itself and this peak disappear at higher pH values. However for acetate buffer there is no oxidation peaks for atenolol. So, polypyrrole films prepared using chronopotentiometry, cyclic voltammetry and NPV are electroactive towards atenolol oxidation in 1M phosphate buffers for pH range from pH 3 to pH 6.
PPy-AMPSNa electrode prepared by the above mentioned methods using phosphate buffer of pH 3 at different atenolol concentrations show a well-defined oxidation peak for atenolol oxidation during differential pulse voltammetry measurments. The amplitude of the peak is enhanced with the increasing of atenolol concentration. The plotting of maximum peak currents versus concentration of atenolol is linear with a good fitting in the range from lxl O’9 to 8 xlO’9 M of atenolol. The minimum detection limit for AMPSNa doped PPy electrode is found to be lxl O’9 M of atenolol. This technique is used to verify the atenolol concentration of commercial lacally avialable tablets.