Determination of Trace Selenium in Plants by Hydride Generation Atomic Fluorescence Spectrometry with Program Temperature- Controlled Graphite Digestion
QIAN Wei, JIANG Qian, WANG Ru-hai, GONG Hua, HAN Yong
Soil and Environment Analysis Center, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
Abstract：Discussed several methods of pretreatment for the determination of selenium were discussed, and a program temperature-controlled graphite digestion method was developed to digest 5 kinds of representative standard plant samples of citrus leaves, tea, cabbage leaves, shrubs and rice. The effect of the pretreatment method of digestion solution, digestion temperature and digestion time on the extraction of selenium was investigated in detail. The instrumental working parameters were optimized. For the reaction conditions of hydride generation atomic fluorescence spectrometry (HG-AFS), the effect of the concentration of KBH4 and HCl on the determination of selenium was emphasized. Not only the effect of the concentration of carrier fiow HCl was considered, but also the effect of the concentration of sample HCl on the determination of selenium was studied. The best method for determination of trace selenium in plant samples by atomic fluorescence spectrometry with program temperature-controlled graphite digestion was established. Results indicated that the recovery of the method of selenium was 87.1%～106.2%, the detection limit was 0.018 μg·L-1 and the relative standard deviation (RSD) was less than 6.0%. In the range of 0～10 μg·L-1 (low standard) and 0～100 μg·L-1 (high standard) fluorescence was linearly related to the concentration of selenium, the coefficient of r was 0.999 9 and r was 0.999 7. Therefore, this method has wide linear range, high sensitivity, low detection limit and good stability, which was very suitable for the determination of trace selenium of plant. And the method was of easy and safe operation, strong practicability, low cost, and low toxicity of chemicals used, so it can be used as a routine analysis method in general laboratory.
[1] Ferguson L R，Karunasinghe N，Zhu S，et al. Mutation Research/Fundamental and Molecular Mechanisms of Mutagenesis，2012，733 (1-2): 100. [2] WANG Kui(王 夔). Trace Elements in Life Science，2nd Edition (生命科学中的微量元素，第2版). Beijing: Chinese Metrology Press(北京: 中国计量出版社), 1996. 650. [3] BAO Jian-min，YU Xiao-yan，LIU Wei，et al(包建民，于晓燕，刘 微，等). Journal of Instrumental Analysis(分析测试学报)，2012，31(7): 804. [4] Reide M E，Strattonb M S，Lillicoc A J，et al. Journal of Trace Elements in Medicine and Biology，2004，18(1): 68. [5] MA Xiu-jie，ZHANG Yue-an(马秀杰，张跃安). Chinese Journal of Public Health(中国公共卫生)，2009，25(8): 1021. [6] Filipe C，Miguel M，Carlos C，et al. Journal of Food Composition and Analysis，2011，24(3): 351. [7] WANG Shi-cheng，WANG Yan-hong，LIU Yan-hui，et al(王世成，王颜红，刘艳辉，等). Food Science(食品科学)，2013，34(04): 183. [8] Sounderajan S，Kumar G K，Udas A C. Journal of Hazardous Materials，2010，175(1-3): 666. [9] Zvonimir S，Jaroslava Svarc-Gajic，Nikola M，et al. Food Chemistry，2005，92(4): 771. [10] CHANG Yin-fu(常银甫). Physical Testing and Chemical Analysis(Part B: Chemical Analysis)(理化检验-化学分册)，2010，46(8): 970. [11] ZHANG Hao，MO Hai-zhen，ZHOU Quan-xia，et al(张 浩，莫海珍，周全霞，等). Food Science(食品科学)，2010，31(14): 211. [12] WANG Bing-tao，XIE Li-qi，LIN Yan-kui，et al(王丙涛，谢丽琪，林燕奎，等). Chinese Journal of Chromatography(色谱)，2011，29(3): 223. [13] HU Liang，DONG Ze-qin，HUANG Xiao-han，et al(胡 良，董泽琴，黄笑寒，等). Chinese Journal of Analytical Chemistry(分析化学)，2011，39(4): 466. [14] GB 5009.93—2010. The People’s Republic of China National Standard(中华人民共和国国家标准). National Food Safety Stsndard Determination of Selenium in Foods(食品安全国家标准-食品中硒的测定).
