State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Meilong RD 130, Shanghai, 200237, China.
Analyst. 2012 Feb 7;137(3):601-7. doi: 10.1039/c1an15909g. Epub 2011 Dec 8.
A colorimetric assay has been developed for parallel detection of Cd(2+), Ni(2+) and Co(2+) utilizing peptide-modified gold nanoparticles (P-AuNPs) as a sensing element based on its unique surface plasmon resonance properties. The functional peptide ligand, CALNNDHHHHHH, was self-assembled on gold nanoparticles (AuNPs) to produce P-AuNPs probe. The P-AuNPs probe could be used to simultaneously detect and showed different responses to the three ions Cd(2+), Ni(2+) and Co(2+) in an aqueous solution based on the aggregation-induced color change of AuNPs. The method showed good selectivity for Cd(2+), Ni(2+) and Co(2+) over other metal ions, and detection limit as low as 0.05 μM Cd(2+), 0.3 μM Ni(2+) or 2 μM Co(2+). To simultaneously (or parallel) detect the three metal ions coexisting in a sample, EDTA and imidazole were applied to mask Co(2+) and Ni(2+) for detecting Cd(2+), glutathione and EDTA were applied to mask Cd(2+) and Co(2+) for detecting Ni(2+), and glutathione and imidazole were applied to mask Cd(2+) and Ni(2+) for detecting Co(2+). Finally, the simple and cost-effective probe could be successfully applied for simultaneously detecting Cd(2+), Ni(2+), and Co(2+) in river water. Because this novel P-AgNPs-based probe design offers many advantages, including simplicity of preparation and manipulation compared with other methods that employ specific strategies, the sensing system shows potential application in the developing region for monitoring water quality.
已开发出一种基于金纳米粒子（AuNPs）独特表面等离子体共振特性的比色测定法，用于同时检测 Cd(2+)、Ni(2+)和 Co(2+)，其使用经肽修饰的金纳米粒子（P-AuNPs）作为传感元件。CALNNDHHHHHH 功能性肽配体自组装在金纳米粒子（AuNPs）上，生成 P-AuNPs 探针。该 P-AuNPs 探针可用于同时检测，并基于 AuNPs 的聚集诱导颜色变化对水溶液中的三种离子 Cd(2+)、Ni(2+)和 Co(2+)表现出不同的响应。该方法对 Cd(2+)、Ni(2+)和 Co(2+)具有良好的选择性，对其他金属离子的检测限低至 0.05 μM Cd(2+)、0.3 μM Ni(2+)或 2 μM Co(2+)。为了同时（或并行）检测样品中共存的三种金属离子，应用 EDTA 和咪唑掩蔽 Co(2+)和 Ni(2+)以检测 Cd(2+)，应用谷胱甘肽和 EDTA 掩蔽 Cd(2+)和 Co(2+)以检测 Ni(2+)，应用谷胱甘肽和咪唑掩蔽 Cd(2+)和 Ni(2+)以检测 Co(2+)。最后，简单且经济高效的探针可成功用于同时检测河水中的 Cd(2+)、Ni(2+)和 Co(2+)。由于与采用特定策略的其他方法相比，这种新型 P-AgNPs 基探针设计具有制备和操作简单等诸多优点，因此该传感系统具有在发展中地区监测水质的潜在应用。
