DIRECT DETERMINATION OF SELENIUM IN WHOLE-BLOOD BY ANODIC-STRIPPING VOLTAMMETRY

Trace quantities of selenium can be determined in the presence of iron , copper and lead using anodic stripping voltammetry, depositing at -0 .60 V in 0.1 M HClO4 and stripping in the anodic direction. Two separa te peaks are observed at -0.25 V and -0.10 V belonging to copper and s elenium, respectively. Sometimes one peak may be observed for both cop per and selenium. In this case one more stripping (without deposition) must be done to obtain separate peaks. After standard addition, two s trippings have to be done also. With this proposed method, 10(-7) M se lenium could be determined as (1.09 +/- 0.03) x 10(-7) M with a 90% co nfidence interval in blood samples without any separation.