偶氮氯膦Ⅲ三波长分光光度法测定乳制品中的钙  

Determination of Calcium in Dairy Products Using Chlorophosphonazo Ⅲ and Three Wavelength Spectrophotometric Method

作　　者：汤家华 陈远[1] 

机构地区：[1]巢湖学院化学与材料工程学院 [2]巢湖学院配位化学研究所,安徽巢湖238000

出　　处：《宜春学院学报》2017年第12期32-35,共4页Journal of Yichun University

摘　　要：以偶氮氯膦Ⅲ(CPAⅢ)为显色剂,建立了三波长分光光度法测定乳制品中钙含量的方法。在p H=3.2的邻苯二甲酸氢钾-盐酸缓冲介质中,在表面活性剂聚乙二醇辛基苯基醚(Triton X-100)作用下,钙与偶氮氯膦Ⅲ(CPAⅢ)可形成一种蓝色配合物。配合物在波长666nm、615 nm处有正吸收峰,在543 nm有负吸收峰,ΔA=A666+A615-A543。钙的质量浓度在0~1.2μg/m L范围内与ΔA有良好的线性关系,表观摩尔吸光系数为3.5×104L·mol-1·cm-1,比单波长灵敏度(ε666=1.5×104L·mol-1·cm-1)提高了133%。平均回收率为94.8%~102%,相对标准偏差为1.0%~3.1%(n=6)。测定结果准确、可靠。A three wavelength spectrophotometry was used for the determination of the contents of calcium in dairy products by using Chlorophosphonazo Ⅲ( CPAⅢ) as a colorimetric reagent. In p H3. 2 buffer solution of C8 H5 KO4-HCl and in presence of surfactant Octyl Phenoxy Poly Ethoxy( Triton X-100),calcium and CPA Ⅲ forms a blue complex,its absorptive peak appeared in 615 nm,666 nm and a negative absorptive peak appeared in 543 nm,ΔA = A666+ A615-A543. ΔA with the mass concentration of calcium had good linear relationship in the rang of 0 ~ 1. 2 μg/m L. Its apparent molar absorptivity was 3. 5 × 104 L·mol-1·cm-1. This data increased by 133%,which compared with the single wavelength method( ε666= 1. 5 × 104 L·mol-1·cm-1). The average recoveries were 94. 8% ~ 102%,and RSDs were 1. 0% ~ 3. 1%( n = 6). The results were accurate and reliable.

关 键 词：钙 偶氮氯膦Ⅲ 三波长 分光光度法 乳制品 

分 类 号：O657[理学—分析化学]