A new ion-imprinted silica gel sorbent for on-line selective solid-phase extraction of dysprosium(III) with detection by inductively coupled plasma-atomic emission spectrometry

摘要

Dysprosium(III)-imprinted thenoyltrifluoroacetone (TTA) modified silica gel sorbent was synthesized by surface imprinting technique and was employed as a selective solid-phase extraction material for flow injection solid-phase extraction on-line coupled with inductively coupled plasma-atomic emission spectrometry (ICP-AES) determination of Dy(III). The largest selectivity coefficient for Dy(III) in the presence of competitive ions such as La(III), Nd(III) and Gd(III) was above 350. The static adsorption capacity and selectivity coefficient of the imprinted sorbent are higher than those of the non-imprinted sorbent and the imprinted TTA modified silica gel sorbent offered a fast kinetics for the adsorption and desorption of Dy(III). With a sample loading flow rate of 2.5 mL min(-1) for 48 s preconcentration and elution flow rate of 1.5 mL min(-1) for 8 s elution, an enrichment factor of 10 and the sample frequency of 40 sample h(-1) were obtained. Detection limits (3a) based on three times standard deviations of the blanks by eight replicates was 0.2 ng mL(-1) and the precisions (R.S.D.s) was 1.5% (n = 8, c = 40 ng mL(-1)). To validate the proposed method, two certified reference materials of GBW07401 soil and GBW07301 a sediment were analyzed and the determined values were in a good agreement with the certified values. The method is rapid, selective, sensitive and applicable to the determination of trace Dy(III) in environmental samples with complicated matrix. (c) 2007 Elsevier B.V. All rights reserved.