الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The electrochemical behavior of the halofuginone was investigated on a
glassy carbon electrode (GLC) in a phosphate buffer solutions, pH=3.0 -10.0.
Cyclic voltammetric (CV) studies indicated that the oxidation process is
irreversible and diffusion-controlled. In addition, halofuginone-imprinted
polypyrrole films were electrochemically prepared on GLC in aqueous solutions
of halofuginone, and NaClO4 as supporting. The halofuginone template
molecule was successfully trapped in the polypyrrole (PPy) film where it created
artificial recognition sites. After extraction of the template, the PPy film acted as
a molecularly imprinted polymer (MIP) for the specific and selective recognition
of halofuginone where as the nonimprinted polymer (NIP) film did not exhibit
any oxidation peak which demonstrates that the imprinted PPy films are specific
towards halofuginone. The effect of pH, monomer and template concentrations,
electropolymerization cycles on the performance of the MIP electrode was
investigated and optimized. The highest anodic signal of halofuginone was
obtained in a phosphate buffer solution of pH 7.0. The calibration curve for
halofuginone at MIP electrode has linear region for a concentration range from
7.5 ×10-9 to 1.0×10-5 M, with a detection limit of 2.5×10-9 M.
The electrochemical behavior of nicergoline (NIC) was studied under the
effect of pH in phosphate buffer solutions supporting electrolytes on SPCE for
the electrochemical oxidation of NIC in aqueous supporting electrolytes over a
pH range from 3.0 to 10.0. The peak potential of anodic peak of NIC is shifted
linearly towards more negative values and peak current also increased up to pH
= 4.0 and afterwards decreased with increasing pH values. But peak potential of
pH 4.0 showed two peaks separated by. For this was selected pH 8 at
measurement process. Cyclic voltammetric studies indicated that the oxidation
process is irreversible and diffusion controlled.