Interfacial phenomena involving Fe(III)-ofloxacin complexes at the water vertical bar 1,2-dichloroethane interface

When the interface formed between an aqueous solution containing ofloxacin, a fluorquinolone antibiotic complexed with Fe(III), and an organic solutio n of a supporting electrolyte in 1,2-dichloroethane is potentiodynamically polarized, interesting electroadsorption phenomena are observed. The narrow negative voltammetric peak observed at much lower potentials than those co rresponding to the diffusional transfer of a triply charged species, the li near response of I-p with upsilon, the difference in the potentials of the positive and negative processes and the shift of this peak towards more neg ative potentials with sweep rate as coverage is increased, provide clear ev idence of an irreversible adsorption-desorption process displaying attracti ve interaction between the adsorbate molecules at high coverage. These resu lts are reinforced by the appearance of an important charge transfer resist ance value in ac measurements. (C) 1999 Elsevier Science S.A. All rights re served.