Study for dependence of transition state with applied potential in electrokinetic reactions of [Mn-antibiotics-cephalothin] system vis-a-vis kinetics of electrode reactions

Electrochemical Laboratory, Department of Chemistry, Dr. Harisingh Gour University, Sagar-4 70 003, Madhya Pradesh, India E-mail : faridkhan58@yahoo. com; farid. fk@rediffmail.com Manuscript received 22 February 2006, accepted 16 October 2006 Polarographic technique was used to study the dependence of 'transition state' witb applied potential between dropping mercury electrode and solution interface of [Mn-antibiotics-cephalothin] system at pH = 7.30 ± 0.01 and µ = I .0 M NaCIO4 at 298 K. The selected antibiotics were doxycycline, chlortetracycline, oxytetracycline, tetracycline, minocycline, amoxicillin and chloramphenicol together with cephalothin formed complexes with Mn2+. The kinetic parameters viz. degree of irreversibility (λ), transfer coefficient (α), diffusion coefficient (D) and rate constant (k) were determined. The values of a varied from 0.41 to 0.54 (0.05) confirmed that the transition state is affected by applied potential