Article révisé par les pairs
Résumé : Mixing carbon paste with a charged lipid, in an appropriate ratio, permitted us to prepare a modified electrode whose surface exhibits interesting characteristics of the constituting lipid. Two negatively charged phospholipids have been selected, namely: asolectin and cardiolipin. By investigating the electrooxidation of several drugs which are known to interact strongly with the lipid component of cellular membranes (adriamycin, epirubicin and promethazine) it was possible to demonstrate markedly different behaviour at the lipid modified carbon paste electrode (LMPCE) depending on the pH of the solution. By analysing the results of linear scan, ac and adsorptive voltammetry and by taking into account literature data on drug-membrane interactions, it was possible to postulate a model of the LMCPE interface with thin layers of lipids covering the graphic particles. The differential capacity measurements as a function of time (fixed potential) and in the presence of increasing amounts of drugs enabled us to point out profound increases in the capacity of the LMPCE in the presence of adriamycin and epirubicin. In addition, the more negatively charged the lipids were, the higher was the capacity increase.