Sayama Y, Hayashibe Y, Fukuda M
Division of Analytical Chemistry, Central Research Institute, Mitsubishi Materials Co., 1-297, Kitabukuro-cho, 330, Saitama, Omiya, Japan.
Anal Bioanal Chem. 1995 Sep;353(2):162-6. doi: 10.1007/s0021653530162.
Traces of cadmium and bismuth in high-purity zinc metal were determined by inductively coupled plasma mass spectrometry (ICP-MS) in combination with flow injection (FI) on-line matrix separation (FI-ICP-MS). The anion-exchange separation method of the potassium iodide (KI) system was applied to the separation of the analytes from the matrix zinc. The analytes, cadmium and bismuth, were adsorbed on the anion-exchange (BIO. RAD AG1-X8) mini-column (1.0 mm i.d.x 100 mm bed length), while the matrix zinc can be completely removed from the anion-exchange resin. The analytes were eluted by 2 mol/l HNO(3) and directly introduced into the ICP-MS. The detection limits (D.L.) obtained by using a single injection (350 microl) were 0.81 and 0.075 ng g(-1) for cadmium and bismuth, respectively. In the case of multi-injection concentration onto the anion-exchange mini-column (five injections 350 microl each), the detection limits could be improved to 0.16 and 0.014 ng g(-1) for cadmium and bismuth, respectively. The reproducibilities of the single injection and the multi-injection method were satisfactory with a relative standard deviation of less than 5% (at the 10 and 1 ng ml(-1) level for the single injection and the multi-injection method, respectively). The method was successfully applied to the determination of trace impurities in four samples of high-purity zinc metal (7 nines grade) and three standard reference materials of high-purity unalloyed zinc samples (from NIST).
采用电感耦合等离子体质谱法（ICP-MS）结合流动注射（FI）在线基体分离技术（FI-ICP-MS）测定了高纯锌金属中镉和铋的痕量元素。应用碘化钾（KI）体系的阴离子交换分离方法将分析物与基体锌分离。分析物镉和铋吸附在阴离子交换（BIO.RAD AG1-X8）微型柱（内径1.0 mm×柱床长度100 mm）上，而基体锌可从阴离子交换树脂上完全除去。分析物用2 mol/L硝酸洗脱并直接引入ICP-MS。单次进样（350 μL）时镉和铋的检出限分别为0.81和0.075 ng g⁻¹。在阴离子交换微型柱上进行多次进样富集（每次进样350 μL，共进样5次）的情况下，镉和铋的检出限可分别提高到0.16和0.014 ng g⁻¹。单次进样和多次进样方法的重现性良好，相对标准偏差均小于5%（单次进样和多次进样方法分别在10和1 ng mL⁻¹水平）。该方法成功应用于4个高纯锌金属样品（99.9999%纯度等级）和3个高纯纯锌标准参考物质（来自美国国家标准与技术研究院）中痕量杂质的测定。
