title: Applications in drug analysis of carbon paste electrodes modified by fatty acids.
abstract: The oxidation of promethazine as a model compound has been studied by adsorptive stripping voltammetry at carbon paste electrodes (CPE). A modification of the carbon paste matrix with fatty acids allows greater preconcentration of the molecule at the electrode surface. Several fatty acids of different chain length have been tested. The modification of the CPE with lauric acid has been successfully applied in the quantitative analysis of promethazine in standard serum samples. The influence of several parameters affecting the accumulation step has been investigated such as: pH, ionic strength, interfering ions, paste composition. The detection limit in phosphate buffer at pH 9.0 (tacc = 5 min) has been found to be 1 x 10(-10) M.
authors.affiliation: Faculty of Sciences, Chemistry Department, Assiut University, Kena, Egypt.
authors.forename: M
authors.initials: M
authors.lastname: Khodari
authors.forename: J M
authors.initials: JM
authors.lastname: Kauffmann
authors.forename: G J
authors.initials: GJ
authors.lastname: Patriarche
authors.forename: M A
authors.initials: MA
authors.lastname: Ghandour
mesh_terms: D002244:Carbon; D004563:Electrochemistry; D004566:Electrodes; D005227:Fatty Acids / Q000032:analysis* / Q000097:blood; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D008055:Lipids / Q000032:analysis; D004364:Pharmaceutical Preparations / Q000032:analysis*; D011398:Promethazine / Q000032:analysis / Q000097:blood; D012996:Solutions
chemical_list: D005227:Fatty Acids; D007202:Indicators and Reagents; D008055:Lipids; D004364:Pharmaceutical Preparations; D012996:Solutions; D002244:Carbon; D011398:Promethazine