Study of the adsorption and surface reduction of cefazolin by cyclic voltammetry

Abstract We have studied the adsorption and heterogeneous reduction of cefazolin by cyclic voltammetry and chronocoulometry with voltammogram integration. The results obtained suggest that, at least at concentrations below 10 −3 M , adsorption of cefazolin is of the Frumkin-type and takes place in a monolayer, with the three rings of the molecule coplanar to the electrode surface. The kinetic results show that the transfer is always irreversible. The variation of the transfer coefficient with pH can be accounted for on the basis of the antibiotic's p K and of the involvement or not of a proton in the rate-determining step.