白沙绿茶和红茶中硒含量的优化测定
|
摘要
采用氢化物发生原子荧光法测定海南白沙绿茶和红茶中的硒含量,研究了仪器条件和还原剂等对硒原子荧光强度的影响。结果表明,最佳仪器条件为光电倍增管负高压300 V,灯电流80 mA;还原剂浓度为1.5%,载流盐酸浓度5%。该方法线性范围0~10μg/L时,与荧光值线性关系好,回归方程为y=75.949x-8.795 4,相关系数r=0.9998。方法检出限是0.024μg/kg,测定标准物质中硒的回收率为97.7%~109.6%。以国家标准物质茶叶(GBW10016)为监控样品,标准物质茶叶测定值与标准值吻合。白沙绿茶和红茶硒元素含量分别是34.4和20.1μg/kg。该方法线性范围宽、灵敏度高、检出限低,可用于茶叶等样品中硒元素含量的准确测定。
In this study the content of selenium in Baisha green and red tea were determined by hydride generation atomic fluorescence spectrometry. The influence factor such as instrument conditions and the concentration of reducing agent were considered. The results showed that the best instrument conditions were the photomultiplier negative pressure 300V, lamp current 80mA; the concentration of reducing agent1.5%, the concentration of hydrochloric acid current carrying 5%. The fluorescence values were good in the method when the linear range was 0 ~ 10μg/L, regression equation was y =75.949x-8.795 4,correlation coefficient, r=0.999 8, the detection limit was 0.024 μg/kg, and the recovery of method was97.7% ~ 109.6%. This method was verified by analyzing the national reference material(GBW10016) and the found value was in good agreement with the certified value. The content of selenium in Baisha green and red tea was 0.0772 μg/kg and 0.0456 μg/kg. The method has wide linear range, high sensitivity, low detection limit, which was very suitable for the determination of trace selenium of tea in general laboratory.
In this study the content of selenium in Baisha green and red tea were determined by hydride generation atomic fluorescence spectrometry. The influence factor such as instrument conditions and the concentration of reducing agent were considered. The results showed that the best instrument conditions were the photomultiplier negative pressure 300V, lamp current 80mA; the concentration of reducing agent1.5%, the concentration of hydrochloric acid current carrying 5%. The fluorescence values were good in the method when the linear range was 0 ~ 10μg/L, regression equation was y =75.949x-8.795 4,correlation coefficient, r=0.999 8, the detection limit was 0.024 μg/kg, and the recovery of method was97.7% ~ 109.6%. This method was verified by analyzing the national reference material(GBW10016) and the found value was in good agreement with the certified value. The content of selenium in Baisha green and red tea was 0.0772 μg/kg and 0.0456 μg/kg. The method has wide linear range, high sensitivity, low detection limit, which was very suitable for the determination of trace selenium of tea in general laboratory.
引文
[1]赵洪进,刘家国,刘艳娟,等.富硒麦芽中硒的氢化物发生-原子荧光光谱法测定[J].现代食品科技,2007(03):72-74.
[2]李明远.微波消解-氢化物原子荧光光谱法测定食品中的微量元素硒[J].光谱实验室,2007(05):618-621.
[3]钱薇,蒋倩,王如海,等.程序控温石墨消解-氢化物原子荧光光谱法测定植物中痕量硒[J].光谱学与光谱分析,2014(01):235-240.
[4]GB 5009.93-2010,食品安全国家标准,食品中硒的测定.
[5]王震,范世华,方肇伦.顺序注射蒸气发生非色散原子荧光光谱法测定环境样品中痕量硒[J].分析化学研究简报,2005(02):195-197.
[6]苟体忠,唐文华,张文华,等.氢化物发生-原子荧光光谱法测定植物样品中的硒[J].光谱学与光谱分析,2012(05):1 401-1 404.
[7]王梅,张红香,邹志辉,等.原子荧光光谱法测定富硒螺旋藻片中不同形态、价态的硒[J].食品科学,2011(06):179-183.
[8]徐永新,雒昆利.氢化物发生原子荧光光谱法对水中总硒含量测试方法改进研究[J].光谱学与光谱分析,2012(02):532-536.
[9]杜明,赵镭,赵广华,等.生物样品中微量硒测定方法的进展[J].理化检验-化学分册,2007(09):797-802.
[10]丁刚,胡家英,周可金.微波消解-原子荧光法测定富硒油菜籽中硒的方法研究[J].湖北民族学院学报(自然科学版),2007(02):195-198.
[2]李明远.微波消解-氢化物原子荧光光谱法测定食品中的微量元素硒[J].光谱实验室,2007(05):618-621.
[3]钱薇,蒋倩,王如海,等.程序控温石墨消解-氢化物原子荧光光谱法测定植物中痕量硒[J].光谱学与光谱分析,2014(01):235-240.
[4]GB 5009.93-2010,食品安全国家标准,食品中硒的测定.
[5]王震,范世华,方肇伦.顺序注射蒸气发生非色散原子荧光光谱法测定环境样品中痕量硒[J].分析化学研究简报,2005(02):195-197.
[6]苟体忠,唐文华,张文华,等.氢化物发生-原子荧光光谱法测定植物样品中的硒[J].光谱学与光谱分析,2012(05):1 401-1 404.
[7]王梅,张红香,邹志辉,等.原子荧光光谱法测定富硒螺旋藻片中不同形态、价态的硒[J].食品科学,2011(06):179-183.
[8]徐永新,雒昆利.氢化物发生原子荧光光谱法对水中总硒含量测试方法改进研究[J].光谱学与光谱分析,2012(02):532-536.
[9]杜明,赵镭,赵广华,等.生物样品中微量硒测定方法的进展[J].理化检验-化学分册,2007(09):797-802.
[10]丁刚,胡家英,周可金.微波消解-原子荧光法测定富硒油菜籽中硒的方法研究[J].湖北民族学院学报(自然科学版),2007(02):195-198.