National Centre for Compositional Characterisation of Materials (CCCM), B.A.R.C., ECIL (P.O.), Hyderbad 500062, India. shekhar
Talanta. 2012 May 15;93:32-6. doi: 10.1016/j.talanta.2012.02.004. Epub 2012 Feb 9.
A method has been developed to improve the sensitivity of the electrolyte cathode discharge atomic emission spectrometry (ELCAD-AES) for mercury determination. Effects of various low molecular weight organic solvents at different volume percentages as well as at different acid molarities on the mercury signal were investigated using ELCAD-AES. The addition of few percent of organic solvent, acetic acid produced significant enhancement in mercury signal. Acetic acid of 5% (v/v) with the 0.2M acidity has been found to give 500% enhancement for mercury signal in flow injection mode. Under the optimized parameters the repeatability, expressed as the percentage relative standard deviation of spectral peak area for mercury with 5% acetic acid was found to be 10% for acid blank solution and 5% for 20 ng/mL mercury standard based on multiple measurements with a multiple sample loading in flow injection mode. Limit of detection of this method was determined to be 2 ng/mL for inorganic mercury. The proposed method has been validated by determining mercury in certified reference materials, Tuna fish (IAEA-350) and Aquatic plant (BCR-060). Accuracy of the method for the mercury determination in the reference materials has been found to be between 3.5% and 5.9%. This study enhances the utility of ELCAD-AES for various types of biological and environmental materials to quantify total mercury at very low levels.
已经开发出一种方法来提高电解质阴极放电原子发射光谱法（ELCAD-AES）测定汞的灵敏度。使用 ELCAD-AES 研究了不同体积百分比和不同酸度的各种低分子量有机溶剂对汞信号的影响。添加少量有机溶剂（如乙酸）可以显著增强汞信号。在流动注射模式下，发现 0.2M 酸度下 5%（v/v）的乙酸可使汞信号增强 500%。在优化的参数下，基于多次测量和多次样品加载，发现 5%乙酸的酸空白溶液中汞的光谱峰面积百分比相对标准偏差的重复性为 10%，20ng/mL 汞标准溶液的重复性为 5%。该方法的检出限为 2ng/mL 无机汞。该方法已通过测定认证参考物质（金枪鱼（IAEA-350）和水生植物（BCR-060）中的汞来验证。该方法在参考物质中测定汞的准确度在 3.5%至 5.9%之间。这项研究增强了 ELCAD-AES 在各种类型的生物和环境材料中用于定量极低水平总汞的实用性。
