Lewis S A
Methods Enzymol. 1988;158:391-402. doi: 10.1016/0076-6879(88)58071-0.
The definitive IDMS method has the advantage of good detection limits and precision. The advent of the new, smaller, easy-to-use GC/MS system should make this method more popular. The fluorometric method remains the method of choice for the determination of selenium in many matrices if the limitations of the method are understood. The newer methods include gas chromatography, HG-AAS, and GFAAS. The gas chromatography methods show promise because of the relatively simple instrumentation needed and the fact that the analyte is separated from the matrix. HG-AAS offers good sensitivity provided care is taken to ensure complete sample digestion and conversion of selenium to selenite. The advent of Zeeman background correction systems for GFAAS has greatly facilitated selenium determinations, particularly in biological matrices where iron and phosphorus are also present. The reference materials now available, used as part of a quality assurance program, should help to ensure accurate determinations, permit method validation, and allow performance evaluation in interlaboratory trials.
权威的同位素稀释质谱法（IDMS）具有检测限低和精密度高的优点。新型、体积更小且易于使用的气相色谱/质谱联用（GC/MS）系统的出现，应会使该方法更受欢迎。如果了解荧光法的局限性，它仍是许多基质中硒测定的首选方法。较新的方法包括气相色谱法、氢化物发生-原子吸收光谱法（HG-AAS）和石墨炉原子吸收光谱法（GFAAS）。气相色谱法因所需仪器相对简单以及分析物能与基质分离而展现出前景。只要注意确保样品完全消解并将硒转化为亚硒酸盐，HG-AAS就能提供良好的灵敏度。GFAAS的塞曼背景校正系统的出现极大地促进了硒的测定，特别是在同时存在铁和磷的生物基质中。现有的参考物质用作质量保证计划的一部分，应有助于确保准确测定、进行方法验证并在实验室间试验中进行性能评估。
