采用氧弹燃烧-离子色谱方法研究茶叶中氟离子的测定。结果表明：用充氧3 MPa的氧弹燃烧分解样品,然后用离子色谱法测定茶叶中氟离子的含量,建立了KOH梯度淋洗程序为5~40 mmol/L,流速为1.0 mL/min。氟离子的线性范围为0.05~30 mg/L,茶叶中氟的检出限为5 µg/kg;平均回收率为90.7%~103.4%,相对标准偏差为0.93%~2.02%;测定国家茶叶标准物质氟含量与标准值相符。结论本方法具有操作简便,检测干扰小,结果准确可靠的优点。
The method of determining total fluoride in tea has been investigated, with oxygen bomb combustion and ion chromatography. The result showed that the sample of tea was burned in the oxygen bomb with 3 MPa purity oxygen, the content of total fluoride was determined directly by means of ion chromatography. The gradient elution procedure was optimized as 5~40 mmol/L and the flow rate as 1.0 mL/min. The linear range of the calibration curve for fluoride was 0.05~30 mg/L with a detection limit of 5 μg/kg. The average recoveries were 90.7%~103.4% with RSD of 0.93%~2.02%. The fluoride in national tea reference material was determined．It was concluded that the advantages of present method are simple operation, high sensitivity and good repeatability.
[1] 张凌云, 陈瑞鸿, 曹顺爱, 等. 茶叶中氟的研究进展[J]. 茶叶, 2002, 28(1): 11~13.
[2] 中国预防医学科学院营养与食品卫生研究所、卫生部食品卫生监督所、四川省绵阳地区卫生防疫站. GB/T5009.18 –2003 食品中氟的测定[S].
[3] 朱正强, 李永权, 张国清, 等. 茶叶中氟的电极法测定相关问题探讨[J]. 预防医学情报杂志, 2006, 22(1): 116~118.
[4] J. M Colina, C F Arias, A Rodriguez.The influence of composition of the TISAB solution on the determination of fluoride in tea infusion[J]. Fluoride, 1990, 23(1): 20~23.
[5] 李宗澧, 刘静. 离子选择电极快速测定植物中氟[J]. 分析化学, 1992, 20(2): 244.
[6] AOAC. Official methods of analysis of the Association of Official Analytical Chemists (15 th ed) [S]. Philadelphia: Association of Official Analytical Chemists, 1990, Section 944108.
[7] W ILKESA J, TALBOT JM. Optimization of total fluoride analysis by capillary gas chromatography. Part Ⅰ: Silica based dental cream[J]. Pharmaceutical Acta Helvetiae, 1996, 71(4): 273~277.
[8] FRANKENBERER W T J. Environmental applications of ion chromatography[J]. J Chromatogram, 1990, 504: 211~245.
[9] TIAN K, DASGUPTA P K, ANDERSON T A.Determination of trace perchlorate in high-salinity water samp-les by ion chromatography with on-line preconcentration and preelution[J]. Anal Chem, 2003, 75: 701~706.
[10] ZHU B H, ZHONG Z X, YAO J.Ion chromatographic determination of trace iodate, chlorite, chlorate, bromide, bromate and nitrite in drinking water using suppressed conductivity detection and visible detection[J]. J Chromatogr, A, 2006, 1118: 106~110.
[11] AR IB IH E, LE BLANC Y J C, ANTONSEN S, et al. Analysis of perchlorate in foods and beverages by ion chromatography coup led with tandem mass spectrometry( IC-ESI-MS/MS)[J]. Anal Chim Acta, 2006, 567: 39~47.
[12] 张吉祥, 周建科, 吴志勇. 离子色谱法测定柿叶中有机酸和无机阴离子[J]. 理化检验: 化学分册, 2002, 38(1): 29~31.
[13] 石元值, 杨亦扬, 阮建云, 等. 用离子色谱法同时测定茶叶中的F-、Cl-、SO4、NO3[J]. 食品科学, 2008, 29(3), 383~385.
[14] 汪显阳, 李鲁玲. 氧弹燃烧-标准加入氟离子选择性电极法测定砖茶中的氟[J]. 茶叶科学, 2006, 26(3): 204~208.
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