An automatically controlled collection/concentration system was incorporated in ICP-AES. This method was applied to the determination of trace multi elements in water samples. An iminodiacetate-type resin, ME-2, was packed in a small column (2 mm i.d. and 40 mm length) for the collection/concentration of multi elements, and the column was installed at a switching valve. The sample used was 20 mL, and its flow rate was 60 μL s
−1. The column being passed through a sample solution was washed with 0.5 mL of water ; the elution was then carried out with 0.75 mL of 2 M HNO
3 flowing at 30 μL s
−1. ME-2 resin adsorbed 29 elements at pH 6 ; 12 elements (V, Co, Ni, Cu, Y, Mo, Cd, Pb, La, Eu, Dy and Ho) could be collected and recovered quantitatively at a concentration range from 0.1 ng mL
−1 to 0.5 ng mL
−1. Of these, 7 elements (V, Co, Ni, Cd, La, Eu and Dy) could be determined at trace level from 0.01 ng mL
−1 to 0.1 ng mL
−1. The detection limits (LODs) were between 0.001 ng mL
−1 (Y, Cd) and 0.079 ng mL
−1 (Mo). The concentration efficiency compared with the signal intensity of a direct measurement was around 100. The sample throughput was about 10 min. The proposed method was successfully applied to river and tap-water samples.
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