The detection of copper ions in aqueous solution using electrochemiluminesc
ence (ECL) is reported. ECL is generated by reducing Cu2+ ions to Cu+ with
hydroxylamine hydrochloride and then complexing with the chelating agent 2,
9-dimethyl-1,10-phenanthroline (dmp) to form Cu(dmp)(2)(+), followed by oxi
dation in the presence of tri-n-propylamine (TPrA). The ECL intensity peaks
a potential corresponding to oxidation of both TPrA and Cu(dmp)(2)(+), ind
icating that the emission is from a Cu(dmp)(2)(+) metal-to-ligand charge tr
ansfer excited state. Conditions for ECL emission were optimized and used t
o generate a calibration curve that was linear over the 0.1-5 mg/l (ppm) ra
nge. The theoretical limit of detection was 6 mug/l (ppb), with a practical
limit of detection of 0.1 ppm. The ECL of several metal ions other than co
pper with dmp, and effects on Cu(dmp)(2)(+) ECL were also examined. (C) 200
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