ADSORPTIVE STRIPPING VOLTAMMETRIC DETERMINATION OF URANIUM WITH CEPHRADINE

Uranium adsorbed with cephradine is reduced on a hanging mercury drop electrode. This property was exploited in developing a highly sensitive stripping voltammetric procedure for the determination of uranium. A detection limit 2 x 10(-9) mol l(-1) (0.5 mu g l(-1)) of uranium ion is obtained with an 180 s accumulation time. Cyclic voltammetry was used to characterize the interfacial and redox behaviour. The effects of various parameters are discussed. Experimental conditions include the use of 5 x 10(-6) mol l(-1) cephradine in 0.05 mol l(-1) sodium perchlorate (pH approximate to 6.5), an accumulation potential of 0.0 V versus SCE and a direct current stripping technique. The response is linear up to 5 x 10(-6) mol l(-1) uranium and the relative standard deviation at 1 x 10(-7) mol l(-1) UO2+ is 4.4%. The effect of other metal ions was investigated.