硫酸肼比浊法测定微量硒.pdf

第27卷第3期
化学研究与应用
Vol 27.No.3
2015年3月
Chemical Research and Application
Mar.,2015
文章编号:1004-1656(2015)03-0398-05
硫酸肼比浊法測定微量硒
谢宇奇,凌绍明,罗夏倩
(百色学院化学与生命科学系,广西百色533000
摘要:依据硒(Ⅳ)在以甘油为稳定剂,盐酸为反应介质的条件下,被过量硫酸肼还原,使体系形成稳定悬浊液
的原理,建立了比浊法测定硒的方法。探讨了盐酸用量、甘油用量、反应温度和反应时间以及硫酸肼用量等5
个关键因素的影响,确定了最佳测定条件。实验结果表明:大量的共存物质不于扰测定。在选定的实验条件
下,线性方程为:△A40m=12.725p+0.0076,在2.0x10-3.2x102mg?mL'范围内线性关系良好,相关系数
(R2)=0.9911方法的检出限为1.2x10-mg?mL'。方法用于测定强化营养盐中总硒,回收率在97.0
103.5%之间,RSD为1.8%。
关词:硒;比浊法;硫酸肼
中图分类号:0657.32文献标志码:A
Hydrazine sulfate turbidimetry determination of trace selenium
XIIE Yu-qi, LING Shao-ming", LUO Xia-qian
( Department of chemistry and Life Science, Baise University, Baise 53300, China)
Abstract: A new nephelomtric method was developed for the determination of selenium. The proposed method is based on the reac-
t on of Se(M )with excess hydrazine ul aa n H mem eae meal selenium which subsequently from stable suspen-
sion in the presence of glycerin used as stabilizer. The influences of five key factors such as dosage of hydrochloric acid and glycer-
ol, reaction temperature and time, and dosage of reducing agent were investigated, and the optimum conditions were determined. A
large number of substances do not interfere with the determination of coexistence. Under the chose conditions, the linear regression
equation was AA m=12. 725 + 0. 76. A good linear relationshi was obtained in 2.010 3.210"mg ml linea
range. The realative coefficient was 9911. The detection limit was 1. 2x 10 mgm . The method used to measure total selenium
of strengthen nutrition salt, RSD is 1.8%, the average recovery is 97.0- 103.5%
Key words: selenium; turbidimetry; hydrazine sulfate
硒( selenium)是一种是包括人在内的许多生硒含量偏低,因此人们通过食补和药补等方式增
物必须的微量元素,具有抗癌、抗氧化、拮抗有害加硒的摄入日益受到重视。但硒过量中毒的剂量
重金属等众多生理功能。研究表明,许多恶性范围很窄,在食品药品中测定硒的含量具有重要
疾病与硒缺乏关系密切,如甲状腺癌、大肠癌、慢的现实意义。
性肺炎、肺结核、克山病、大骨节病、生殖系统疾病
由于硒在生物体内和环境中的存在形态多样
等4。由于我国大部分国土处于低硒带,土壤中且复杂,研究人员不断创新富集和分离技术,利用
收稿日期:2014-08-25;修回日期:2014-11-15
基金项目:桂西区域生态环境分析和污染控制重点实验室资助;广西高校科学技术研究项目(LX201444)资助
联系人简介:凌绍明(1963-),男,教授,主要从事光谱分析研究。E-mail:lingshaomingc@sohu.com