电热蒸发-微波等离子体炬全谱仪检测血清中钙、镁和铁

Direct Determination of Ca,Mg and Fe in Serum by Using a Simultaneous Microwave Plasma Torch Spectrometer Coupled with an Improved Electrothermal Vaporization Device

采用电热蒸发与微波等离子体炬(MPT)全谱仪联用的仪器设备,并改进了以前的电热蒸发装置,对血清样品中Ca、Mg和Fe的检测采用直接进样的方式,省去了繁琐的样品处理过程。通过控制操作条件,消除了Na元素和一些有机成分的基体干扰。本方法具有用样量少(微升级)、操作简单、检测成本低、分析速度快等优点。实验还对操作条件进行了优化,在优化的条件下,加入5μL样品时,对Ca、Mg和Fe的检出限(3σ)分别为0.04、0.4和4.6μg/L;相对标准偏差则均小于5%(n=6);在检测范围内各元素校正曲线呈线性。本法已成功应用于血清中Ca、Mg和Fe含量的测定。

A novel procedure for the direct determination of Ca, Mg and Fe in serum using an improved electrothermal vapori.zation simultaneous microwave plasma torch spectrometer （ETV-MPT） was described. The background emission and spectral interferences caused by tantalum ablation were reduced by coating the coil with tantalum carbide. The proposed method eliminated the need for a lengthy sample digestion procedure, and avoided the matrix interference. The operating parameters were studied and optimized. The detection limits were 0. 04, 0.4 and 4.6μg/L for Ca, Mg and Fe, respectively, and the relative standard deviations were less than 5 % （ n = 6）. The new system was successfully applied to the analysis of practical serum sample.