Maheswari Mohan A, Subramanian Mandakolathur S
Indian Institute of Technology, Department of Chemistry, Chennai 600 036, India.
J AOAC Int. 2003 Nov-Dec;86(6):1218-24.
A new polychelatogen, AXAD-16-1,2-diphenylethanolamine, was developed by chemically modifying Amberlite XAD-16 with 1,2-diphenylethanolamine to produce an effective metal-chelating functionality for the preconcentration of Mn(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(II) and their determination by flame atomic absorption spectrometry. Various physiochemical parameters that influence the quantitative preconcentration and recovery of metal were optimized by both static and dynamic techniques. The resin showed superior extraction efficiency with high-metal loading capacity values of 0.73, 0.80, 0.77, 0.87, 0.74, and 0.81 mmol/g for Mn(II), Ni(II), Cu(II), Zn(II), Cd(II), and Pb(II), respectively. The system also showed rapid metal-ion extraction and stripping, with complete saturation in the sorbent phase within 15 min for all the metal ions. The optimum condition for effective metal-ion extraction was found to be a neutral pH, which is a great advantage in the preconcentration of trace metal ions from natural water samples without any chemical pretreatment of the sample. The resin also demonstrated exclusive ion selectivity toward targeted metal ions by showing greater resistivity to various complexing species and more common metal ions during analyte concentration, which ultimately led to high preconcentration factors of 700 for Cu(II); 600 for Mn(II), Ni(II), and Zn(II); and 500 for Cd(II) and Pb(II), arising from a larger sample breakthrough volume. The lower limits of metal-ion detection were 7 ng/mL for Mn(II) and Ni(II); 5 ng/mL for Cu(II), Zn(II), and Cd(II), and 10 ng/mL for Pb(II). The developed resin was successful in preconcentrating metal ions from synthetic and real water samples, multivitamin-multimineral tablets, and curry leaves (Murraya koenigii) with relative standard deviations of < or = 3.0% for all analytical measurements, which demonstrated its practical utility.
一种新型多螯合剂AXAD - 16 - 1,2 - 二苯基乙醇胺，是通过用1,2 - 二苯基乙醇胺对Amberlite XAD - 16进行化学改性而开发的，用于为Mn(II)、Ni(II)、Cu(II)、Zn(II)、Cd(II)和Pb(II)的预富集产生有效的金属螯合功能，并通过火焰原子吸收光谱法对其进行测定。通过静态和动态技术优化了影响金属定量预富集和回收率的各种物理化学参数。该树脂对Mn(II)、Ni(II)、Cu(II)、Zn(II)、Cd(II)和Pb(II)分别显示出优异的萃取效率，其高金属负载量值分别为0.73、0.80、0.77、0.87、0.74和0.81 mmol/g。该体系还显示出快速的金属离子萃取和洗脱，所有金属离子在15分钟内吸附剂相完全饱和。发现有效萃取金属离子的最佳条件是中性pH值，这对于从天然水样中预富集痕量金属离子而无需对样品进行任何化学预处理来说是一个很大的优势。该树脂在分析物浓缩过程中对各种络合物和更常见的金属离子表现出更大的抗性，从而对目标金属离子表现出独特的离子选择性，最终由于更大的样品穿透体积，Cu(II)的预富集因子高达700；Mn(II)、Ni(II)和Zn(II)为600；Cd(II)和Pb(II)为500。金属离子的检测下限分别为：Mn(II)和Ni(II)为7 ng/mL；Cu(II)、Zn(II)和Cd(II)为5 ng/mL，Pb(II)为10 ng/mL。所开发的树脂成功地从合成水样和实际水样、多种维生素 - 多种矿物质片剂以及咖喱叶（九里香）中预富集了金属离子，所有分析测量的相对标准偏差≤3.0%，证明了其实际应用价值。
