Husáková Lenka, Urbanová Iva, Šafránková Michaela, Šídová Tereza
Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573 HB/D, CZ-532 10 Pardubice, Czech Republic.
Department of Analytical Chemistry, Faculty of Chemical Technology, University of Pardubice, Studentska 573 HB/D, CZ-532 10 Pardubice, Czech Republic.
Talanta. 2017 Dec 1;175:93-100. doi: 10.1016/j.talanta.2017.07.031. Epub 2017 Jul 11.
In this work a simple, efficient, and environmentally-friendly method is proposed for determination of Be in soil and sediment samples employing slurry sampling and high-resolution continuum source electrothermal atomic absorption spectrometry (HR-CS-ETAAS). The spectral effects originating from SiO species were identified and successfully corrected by means of a mathematical correction algorithm. Fractional factorial design has been employed to assess the parameters affecting the analytical results and especially to help in the development of the slurry preparation and optimization of measuring conditions. The effects of seven analytical variables including particle size, concentration of glycerol and HNO for stabilization and analyte extraction, respectively, the effect of ultrasonic agitation for slurry homogenization, concentration of chemical modifier, pyrolysis and atomization temperature were investigated by a 2 replicate (n = 3) design. Using the optimized experimental conditions, the proposed method allowed the determination of Be with a detection limit being 0.016mgkg and characteristic mass 1.3pg. Optimum results were obtained after preparing the slurries by weighing 100mg of a sample with particle size < 54µm and adding 25mL of 20% w/w glycerol. The use of 1μg Rh and 50μg citric acid was found satisfactory for the analyte stabilization. Accurate data were obtained with the use of matrix-free calibration. The accuracy of the method was confirmed by analysis of two certified reference materials (NIST SRM 2702 Inorganics in Marine Sediment and IGI BIL-1 Baikal Bottom Silt) and by comparison of the results obtained for ten real samples by slurry sampling with those determined after microwave-assisted extraction by inductively coupled plasma time of flight mass spectrometry (TOF-ICP-MS). The reported method has a precision better than 7%.
本研究提出了一种简单、高效且环保的方法，采用悬浮液进样和高分辨率连续光源电热原子吸收光谱法（HR-CS-ETAAS）测定土壤和沉积物样品中的铍。识别了源自SiO物种的光谱效应，并通过数学校正算法成功校正。采用分数因子设计评估影响分析结果的参数，特别是有助于悬浮液制备的开发和测量条件的优化。通过2重复（n = 3）设计研究了七个分析变量的影响，包括分别用于稳定和分析物提取的粒度、甘油浓度和硝酸浓度、用于悬浮液均质化的超声搅拌效果、化学改进剂浓度、热解温度和原子化温度。使用优化的实验条件，该方法可测定铍，检测限为0.016mg/kg，特征质量为1.3pg。通过称取100mg粒度<54μm的样品并加入25mL 20% w/w甘油制备悬浮液后，获得了最佳结果。发现使用1μg铑和50μg柠檬酸对分析物稳定效果令人满意。使用无基体校准获得了准确的数据。通过分析两种有证标准物质（NIST SRM 270 "海洋沉积物中的无机物" 和IGI BIL-1 "贝加尔湖底淤泥"）以及比较通过悬浮液进样对十个实际样品获得的结果与通过微波辅助萃取后用电感耦合等离子体飞行时间质谱法（TOF-ICP-MS）测定的结果，证实了该方法的准确性。所报道的方法精密度优于7%。
