Study on volatilization of ytterbium as 1-(2-pyridylazo)-2-naphthol chelate from electrothermal vaporizer for sample introduction in inductively coupled plasma atomic emission spectrometry

Based on the formation of a volatile 1-(2ʹ-pyridylazo)-2-naphthol (PAN) chelate, a novel method was described for the determination of trace ytterbium by electrothermal vaporization (ETV)–inductively coupled plasma atomic emission spectrometry (ICP-AES). It was found that in the presence of PAN, the trace Yb was quantitatively vaporized from a graphite furnace into ICP at a low temperature of 1100 °C. The main factors affecting the formation and vaporization of the YbPAN chelate were investigated in detail. Under the optimized conditions, the 3(sigma) detection limit of Yb for this method was 0.4 ng ml^-1 and the relative standard deviation (R.S.D.) for 0.1 (mu)g ml^-1 Yb was 3.7% (n=9, v=10 (mu)l). The linear range of calibration spanned three orders of magnitude. The content of Yb in the standard reference material (shrub, GBW 07603) determined by the proposed method was in good agreement with the certified value.