摘要
采用HNO3-H2O2为消化剂,利用微波消解技术处理酵母样品,在乳化剂OP的存在下,以5-Br-PADAP为显色剂测定了酵母中的微量锌。实验中对微波消解样品的条件、显色体系的酸度、试剂用量以及共存离子的干扰进行了研究。实验表明:微波消解能完全消化样品,锌与5-Br-PADAP形成稳定的络合物,在波长λ=556处有最大吸收峰,锌量在0～12μg/25mL范围内符合比尔定律,络合物的表观摩尔吸光系数为1.16×105 L·mol-1.cm-1。本法已用于酵母粉中微量锌的测定,分析结果与AAS具有良好的一致性。
The spectrophotometric determination of microamount of zinc in yeast powder with 2-（5-bromo-2-pyridylazo）-5-diethylaminophenol （5-Br-PADAP） in the presence of OP was studied. The sample were digested more effectively by HNO3 and H2O2 in a closed-vessel. The effects of digestion time , pressure were researched and analytical conditions optimized. The interferences of coexistent elements in yeast for the determination of Zinc were investigated. The results showed that the maximum absorption wavelength of the complex formed by Zn with 5-Br-PADAP was located at 556 nm. The apparent molar absorptivity was 1.16×10^5 L · mol^-1 · cm^-1.Beer＇s law was obeyed in the concentration range of 0 ～ 12 μg/25 mL for Zinc. Other interfence ions were eliminated by sodium citrate and sulfourea as masking agents. The proposed method has been applied to the determination of Zn in yeast samples with satisfactory, and results agreed with those provided by AAS.
出处
《武汉工业学院学报》
CAS
2007年第4期45-47,共3页
Journal of Wuhan Polytechnic University
