Fan Zhefeng, Hu Bin, Jiang Zucheng, Li Shengqing
Department of Chemistry, Wuhan University, 430072 Wuhan, P R China.
Anal Bioanal Chem. 2004 Jan;378(2):456-9. doi: 10.1007/s00216-003-2314-2. Epub 2003 Dec 5.
A new method for inductively coupled plasma atomic emission spectrometry (ICP-AES) determination of trace Sc and Y, based on gaseous compound introduction into the plasma as their thenoyltrifluoroacetone (TTA) complexes by electrothermal vaporization was developed. Using the reagent TTA as chemical modifier can not only enhance the analytical signals, but also reduce the vaporization temperature. At a temperature of 1,000 degrees C the trace Sc and Y can be vaporized completely into ICP. The factors affecting the formation of the chelate and its vaporization behavior, such as drying time, vaporization temperature/time, reaction medium and the amount of TTA, were investigated in detail. Under the optimized conditions (drying temperature/time 100 degrees C/10 s, vaporization temperature/time 1,000 degrees C/4 s), the limits of detection for Sc and Y were 19 pg and 34 pg (3sigma), respectively, and the relative standard deviations for Sc and Y were 4.2% (cSc=0.2 microg mL(-1); n=7) and 2.6% (cY=0.5 microg mL(-1); n=7). The linear ranges of the calibration graphs cover three orders of magnitude. The method was applied to the analysis of the biological reference materials (GBW 07602, bush branches and leaves; GBW 07604, poplar leaves), and the results obtained were in good agreement with the certified values.
建立了一种电感耦合等离子体原子发射光谱法(ICP-AES)测定痕量钪和钇的新方法,该方法基于通过电热蒸发将气态化合物以其噻吩甲酰三氟丙酮(TTA)配合物的形式引入等离子体。使用试剂TTA作为化学改性剂不仅可以增强分析信号,还可以降低蒸发温度。在1000℃的温度下,痕量钪和钇可以完全蒸发进入ICP。详细研究了影响螯合物形成及其蒸发行为的因素,如干燥时间、蒸发温度/时间、反应介质和TTA的用量。在优化条件下(干燥温度/时间100℃/10 s,蒸发温度/时间1000℃/4 s),钪和钇的检出限分别为19 pg和34 pg(3σ),钪和钇的相对标准偏差分别为4.2%(cSc = 0.2 μg mL⁻¹;n = 7)和2.6%(cY = 0.5 μg mL⁻¹;n = 7)。校准曲线的线性范围覆盖三个数量级。该方法应用于生物标准物质(GBW 07602,灌木枝叶;GBW 07604,杨树叶)的分析,所得结果与认定值吻合良好。