摘要
以3,3′-二氨基联苯胺(DAB)为显色剂,研究了分光光度法测定云南普洱茶中微量元素硒的条件。实验结果表明,以EDTA-2Na为掩蔽剂,显色pH2.5,显色剂用量为6 mL,萃取pH6,络合物在10～120 min能稳定存在,在416 nm下可直接测定吸光度。在优化获得的测定条件下,实验测得标准曲线为:y=0.00491x+0.00105,相关系数r=0.99575,线性范围为0～10.10μg/10mL。回收率为85.1%～105.0%,RSD为1.71%。该方法操作简便,成本低廉,非常适合日常分析。结果表明云南普洱茶中含有较丰富的硒。
Using 3,3＇-diaminobenzidine（DAB） as selenium organic reagent,the author studied the deter-mination conditions of selenium in Yunnan Pu＇er tea by spectrophotometry.The results showed that,using ethylenediamine tertaacetic acid disodium salt（EDTA-2Na） as screening agent,the complex was allowed to stand for 10～120 min with chromogenic agent 6 mL at color pH 2.5 and extraction pH 6.The solution was used to determine the absorbance values with UV spectrophotometry at 416 nm.This method had a good linear relationship at a range of 0～10.10 μg/10 mL.Linear equation was y=0.00491x＋0.00105 and the correlation coefficient was 0.99575.The recovery was 85.1%～105.0%.RSD was 1.71%.The results showed that it was simple,low cost and was suitable for daily analysis.The results showed that Yunnan Pu＇er tea contains rich selenium.
出处
《食品科技》
CAS
北大核心
2010年第12期263-266,共4页
Food Science and Technology
基金
云南省自然科学基金项目(2005C0078M)
