Determination of copper in human plasma by stripping potentiometry on a mercury film electrode in ethylenediamine medium

The use of ethylenediamine improves the determination of copper by potentiometric stripping analysis on a mercury film electrode, with respect to the usual determination method in acidic medium. The influence of chemical and methodological parameters is discussed, and the reliability of the method is checked with certified reference materials. Influence of the acid digestion protocol in open and high pressure closed vessels is investigated. The method developed has been applied to the measurement of the copper level in mineralized human plasma samples. The results have been compared with those obtained by electrothermal atomic absorption spectroscopy in a graphite furnace.