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

When the interface formed between an aqueous solution containing ofloxacin, a fluorquinolone antibiotic complexed with Fe(III), and an organic solution 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 corresponding to the diffusional transfer of a triply charged species, the linear 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 negative potentials with sweep rate as coverage is increased, provide clear evidence of an irreversible adsorption-desorption process displaying attractive interaction between the adsorbate molecules at high coverage. These results are reinforced by the appearance of an important charge transfer resistance value in ac measurements. (C) 1999 Elsevier Science S.A. All rights reserved.