Sensitive second derivative waves of Cu(Ⅱ), Pb(Ⅱ), Cd(Ⅱ), Ni(Ⅱ), Zn(Ⅱ), Fe(Ⅱ) and Mn(Ⅱ) can form in the substrate solution(pH=9.26) containing NH3, NH4Cl, gelatin and ascorbic acid, and the peak potentials of the polarogram of the seven ions are about -0.48, -0.63, -0.79, -1.04, -1.28, -1.44 and -1.60 V, respectively. Therefore, a new method for simultaneous determination of the seven micro-elements in aqueous solutions was developed.The operation of the method is rapid, simple and convenient. The method was used successfully in rapid and simultaneous determination of 7 microelements in Chinese Traditional Medicines.
