作者：谭和平, 周黎黎

作者单位：中国测试技术研究院, 茶叶标准与检测技术四川省重点实验室, 四川 成都 610021

关键词：茶叶; 氟化物; 离子选择电极法; 离子色谱法; 分光光度法

摘要：

为比较氟离子选择电极法、分光光度法、离子色谱法3种方法测定茶叶中氟化物含量的异同,选取低氟、中氟、高氟3种浓度水平的4类茶样共计12份,分别用上述3种方法分析并进行其检出限、测定结果、回收率、精密度的比较。结果显示:3种方法在各自检测区间内均有较好的准确度和精密度,但氟离子选择电极法检出限较其余两种方法高,不适合分析低氟的茶叶样品;分光法操作繁琐,试剂毒性大;采用离子色谱法分析茶叶中的氟化物,可以涵盖各种浓度水平的茶样,并且操作简单,可以同时测定多种阴离子。

Detection assay of fluorine content in tea

TAN He-ping, ZHOU Li-li

Standard and Testing Technology of Tea Key Laboratory of Sichuan Province, National Institute of Mearsurement and Testing Technology, Chengdu 610021, China

Abstract: Three different determination methods of fluoride in tea were studied including ion selective electrode, ultraviolet spectrophotometry and ion chromatography. Four types of tea samples (total 12) with three fluorine levels(low, middle and high) were tested by the three different methods, and the limit of detection, recovery rate, precision and sample results were studied. The results show that all the three different methods had good accuracy and precision. However, the fluoride ion selective electrode method is not suitable for low fluoride in tea samples because of the higher limit of detection than the other two methods, and the ultraviolet spectrophotometric method has some drawbacks such as time-consuming and high reagents toxicity. The ion chromatography method is recommended as the primary method to measure the fluoride in tea, because the method has lots of advantage such as simultaneous determination of various ions, wide linear range, and simple operation.

Keywords: tea; fluorine; ion selective electrode method; ion chromatography; ultraviolet spectrophotometry

2014, 40(5): 58-60  收稿日期: 2014-2-17;收到修改稿日期: 2014-5-5

基金项目: 科技部科技基础项目(2004DEA71180);四川省科技支撑计划项目(2009NZ0015);四川省科技支撑计划项目(2006G11-003)

作者简介: 谭和平(1957-),男,重庆市人,研究员,享受国务院政府津贴专家,从事茶学研究。

参考文献

[1] USEPA 816-F-03-0162003 National Primary and Secondary Drinking Water Regulations[S].
[2] GB/T 21728-2008砖茶含氟量的检测方法[S]. 北京:中国标准出版社,2008.
[3] GB/T 5009.18-2003食品中氟的测定[S]. 北京:中国标准出版社,2003.
[4] 谭和平,周黎黎,徐文平,等. 强疏水性AS-15色谱柱测定茶叶中F^-、Cl^-、NO₃^-、PO₄^3-、SO₄^2-、BrO₃^-、Br^-、NO₂^-的研究[J]. 中国测试,2011,37(6):49-52.
[5] 陈魏,胡德聪,王惠,等. 蔬菜中氟的测定方法研究[J]. 检验检疫学刊,2012,5(22):36-39.
[6] 杨国栋. 电极法和离子色谱法测定生活饮用水中氟化物的比较[J]. 中国卫生检验杂志,2005,8(15):977-978.
[7] 张晓旭,孙爱峰. 电极法和离子色谱法测定生活饮用水中氟化物的信度比较[J]. Guide of China Medicine,2012,10(28):398-399.
[8] 张志瑜,戴国钧. 微量氟测定的三种数据分析计算方法比较[J]. 中国地方病学杂志,1996,3(15):178-179.
[9] 王婕. 电极法测定水中氟化物的注意事项[J]. 科技资讯,2012(5):95.