A rapid and sensitive colorimetric assay method for Co2+ based on the modified Au nanoparticles (NPs): understanding the involved interactions from experiments and simulations.
A rapid and sensitive colorimetric assay method for Co2+ based on the modified Au nanoparticles (NPs): understanding the involved interactions from experiments and simulations.
复制标题
DOI：
10.1016/j.talanta.2012.03.039
复制
发表时间：
2012-03
期刊：
影响因子：
6.1
通讯作者：
Yumin Leng;Fu-Li Zhang;Yujie Zhang;Xiaoqin Fu;Yanbo Weng;Liang Chen;A. Wu
中科院分区：
文献类型：
--
作者：
Yumin Leng;Fu-Li Zhang;Yujie Zhang;Xiaoqin Fu;Yanbo Weng;Liang Chen;A. Wu
我们之前报道了一种基于巯基乙酸 (TGA) 功能化十六烷基三甲基溴化铵 (CTAB) 修饰的金纳米粒子的 Co2+ 比色测定方法。但3×10−7M的检出限仍高于饮用水卫生标准（6.8×10−8M）。此外，改性剂与Au NPs之间以及改性剂-Au NPs与Co2+之间的相互作用仍有待澄清和证实。因此，在本研究中，对修饰的Au NPs溶液进行透析，并将其检测限优化为5×10−10M。在实验表征和理论计算中研究了改性剂与 Au NP 之间以及改性剂-Au NP 与 Co2+ 之间的相互作用，一致证实 Au NP 是通过 Au-S 键被带负电的阴离子 [SCH2CO2]2− 改性的，而 Co2+ 是通过 CoO 螯合键被改性剂-Au NP 识别的。 X射线光电子能谱(XPS)结果表明CTAB和Co2+之间没有形成化学键。此外，使用修饰的 Au NPs 进行 Co2+ 比色测定已被证明是一种快速、非常灵敏和高选择性的方法。该方法的验证是通过分析经过认证的参考物质 GSBZ 50030-94 进行的。
We previously reported a colorimetric assay method for Co2+based on the thioglycolic acid (TGA) functionalized hexadecyl trimethyl ammonium bromide (CTAB) modified Au NPs. However, the detection limit of 3×10−7M was still higher than that of the sanitary standard for drinking water (6.8×10−8M). In addition, the interactions between the modifier and Au NPs, and between the modifier-Au NPs and Co2+remain to be clarified and confirmed. Thus, in the present study, the modified Au NPs solution was dialyzed and its detection limit was optimized to be 5×10−10M. The interactions between the modifier and Au NPs, and between the modifier-Au NPs and Co2+were investigated in both experimental characterizations and theoretical calculations, consistently confirming that the Au NPs were modified by the negatively charged anions of [SCH2CO2]2−through Au–S bonds and Co2+was recognized by the modifier-Au NPs through CoO chelate bonds. The results of X-ray photoelectron spectroscopy (XPS) suggest that there were no chemical bonds formed between CTAB and Co2+. Moreover, the colorimetric assay of Co2+using the modified Au NPs has been proved to be a rapid, very sensitive and highly selective method. The validation of the method was carried out by analysis of a certified reference material, GSBZ 50030-94.