Electrode kinetics and ternary complex formation of [CdII-antibioticsvitamin- B1] system vis-a-vis kinetics of electrode reaction

Electrochemical Laboratory. Department of Chemistry, Dr. H. S. Gour University. Sagar-470 003, Madhya Pradesh. India E-mail : faridkhan58@yahoo.com; farid. fk@rediffmail.com Manuscript received 18 December 2004, revised 26 September 2005, accepted 26 October 2005 Polarographic technique was used to study the ternary complex formation of CdII with neomycin, chlurtelracycline, oxy-tetracycline, tetracycline, penicillin-V and penicillin-G as primary ligands and ,·itamin-B1 as a secondary ligand at pH = 7.30 ± 0.01 and μ = 1.0 M KNO3 at 298 K. The nature of current voltage curves was rcversible and diffusion controlled. CdII formed 1 : 1 : 1, 1 : 1 : 2 and 1 : 2 : 1 complexes with these drugs as confirmed by Schaap and McMaster method. The sequence of stability constants of complexes was neomycin < chlortetracycline < oxytetracycline < tetracycline < penicillin-V < penicillin-G that can be explained on the basis of nature of ligands and steric hindrance between metal and ligands