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目的:为了探讨淡竹叶中多种微量元素的同时、快速测定方法。方法:淡竹叶样品经过微波消解处理后,用全反射X射线荧光(TXRF)分析单一内标法同时测定其中的K、Ca、Fe、Co、Ni、Mn、Cu和Zn等微量元素。结果:确立了微波消解法作为前处理方法的最佳条件:100℃保持3 min,以5℃/min的速率升温至180℃,然后保持50 min。用微波消解-TXRF法测定了花粉标准物质中9种微量元素,并计算得到了TXRF测定淡竹叶中这8种元素的仪器检出限(LLD)范围为:0.002 mg/L(Co、Ni、Cu、Zn)～0.054 mg/L(K),方法检出限(LDM)范围为:0.004 mg/kg(Co、Ni、Cu、Zn)～0.122 mg/kg(K)。微波消解-TXRF测定各元素的相对标准偏差(RSD)在1.5%(Mn)～4.4%(Co)之间。结论:该方法操作简单、样品需用量少、检出限低,可适用于淡竹叶中多种元素的快速、同时测定。
Objective: In order to investigate the simultaneous, rapid determination of trace elements in light bamboo leaves. Methods: The samples of light bamboo leaves were subjected to microwave digestion, and the trace elements such as K, Ca, Fe, Co, Ni, Mn, Cu and Zn were simultaneously determined by total internal reflection spectrometry with total reflection X-ray fluorescence (TXRF) Results: The optimum conditions of microwave digestion as the pretreatment method were as follows: keeping at 100 ℃ for 3 min, raising the temperature to 180 ℃ at the rate of 5 ℃ / min and holding for 50 min. The nine trace elements in pollen reference materials were determined by microwave digestion-TXRF method, and the limit of detection (LLD) of the eight elements in the light bamboo by TXRF was calculated as 0.002 mg / L (Co, Ni, Cu, Zn) ~ 0.054 mg / L (K). The limit of detection (LDM) ranged from 0.004 mg / kg to 0.122 mg / kg. The relative standard deviation (RSD) of each element in microwave digestion-TXRF was between 1.5% (Mn) and 4.4% (Co). Conclusion: The method is easy to operate, requires less sample and has lower detection limit. It can be applied to the rapid and simultaneous determination of various elements in light bamboo leaves.