Determination of Cu2+ in Drinking Water Based on Electrochemiluminescence of Ru(phen)32+ and Cyclam

A convenient and simple electrochemiluminescence (ECL) method was employed to detect trace amounts of Cu2+ in drinking water. This method is based on the inhibitory effect of Cu2+ on the ECL of Ru(phen)(3)(2+) and 1,4,8,11-tetraazacyclotetradecane (cyclam) system. ECL intensity of Ru(phen)(3)(2+) was considerably enhanced by the addition of cyclam because of the ECL reaction between them. The ECL intensity of Ru(phen)(3)(2+)/cyclam system rapidy decreased with the addition Cu2+ because of the formation of chelate complex [Cu(cyclam)](2+). Good linear response (R-2=0.9948) was obtained at Cu2+ concentration of 1.0x10(-9)-1.0x10(-5)molL(-1) at glassy carbon electrode in 0.1molL(-1) phosphate buffer (pH9.0). Observed detection limit of 4.8x10(-10)molL(-1) satisfied the maximum contaminant level goal (MCLG) for Cu2+ set by the US Environmental Protection Agency (US EPA). Applicability of the proposed method was verified by the good reproducibility and stability of the method when applied to determine Cu2+ in tap water and simulated wastewater. Thus, a novel ECL detection method was developed for Cu2+ detection.