THE ELECTROCHEMICAL BEHAVIOR OF A LARGE RING LACTONE ANTIBIOTIC,MIDECAMYCIN

In the system of K₂HPO₄ or NH₃aqueous solution containing 10%(V/V)alcohol ,the voltammetric waves of midecamycin showed two peaks, but only one peak in NaOH baseelectrolyte.The first peak corresponds to the reduction of an aldehyde group and the second peak is thecatalytic adsorption hydrogen wave. The pH of the solution affects strongly both peakS.Experimentalresults showed that the voltammetric wave of midecamycin has adsorption and the polarographic proce-sses of both peaks are irreversible,The peak currents of both peaks are directly proportional to theconcentration of midecamycin. The linear ranges are 3×10^-6～3×10^-5 mol·L^-1 and 1×10^-7～4×10^-5mol·L^-1and the detection limits are 1×10^-6mol·L^-1 and 5×10^-8 mol·L^-1,respectively.It can be used for the determination of midecamycin. The properties of the peaks and theelectrode mechanism have been studied and some physical constants were determined.