Natural Products Research Center, Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, Sichuan, 610041, China.
Biosens Bioelectron. 2011 Jun 15;26(10):4064-9. doi: 10.1016/j.bios.2011.03.033. Epub 2011 Apr 2.
A simple, cost-effective and rapid colorimetric method for any or all of Hg(2+), Pb(2+) and Cu(2+) detection using papain-functionalized gold nanoparticles (P-AuNPs) has been developed. Papain is a protein with seven cystein residues, which can selectively bind with Hg(2+), Pb(2+) and Cu(2+). We functionalized gold nanoparticles with papain. The P-AuNPs could be used to simultaneously detect Hg(2+), Pb(2+) and Cu(2+), and showed different responses to the three ions in an aqueous solution based on the aggregation-induced color change of gold nanoparticles. The P-AuNPs displayed the most obvious response to mercury ions in water in contrast to lead and copper ions, and the real water sample analysis verified the conclusion. The sensitivity of the detection system was influenced by the pH of the P-AuNPs solution, the concentration of P-AuNPs and the size of gold nanoparticles, and we found that larger gold nanoparticles contributed to more sensitive results. The detection system can detect as low as 200 nM Hg(2+), Pb(2+) or Cu(2+) using 42 nm gold nanoparticles. We expect our approach to have wide-ranging applications in the developing region for monitoring water quality in some areas.
已经开发出一种使用木瓜蛋白酶功能化金纳米粒子（P-AuNPs）用于检测 Hg(2+)、Pb(2+) 和 Cu(2+) 的任何或所有离子的简单、经济高效且快速的比色法。木瓜蛋白酶是一种含有七个半胱氨酸残基的蛋白质，可选择性地与 Hg(2+)、Pb(2+) 和 Cu(2+)结合。我们用木瓜蛋白酶功能化了金纳米粒子。P-AuNPs 可用于同时检测 Hg(2+)、Pb(2+) 和 Cu(2+)，并根据金纳米粒子的聚集诱导颜色变化对水溶液中的三种离子表现出不同的响应。与铅和铜离子相比，P-AuNPs 对水中的汞离子表现出最明显的响应，实际水样分析验证了这一结论。检测系统的灵敏度受 P-AuNPs 溶液的 pH 值、P-AuNPs 的浓度和金纳米粒子的大小的影响，我们发现较大的金纳米粒子有助于获得更灵敏的结果。该检测系统可以使用 42nm 金纳米粒子检测低至 200nM 的 Hg(2+)、Pb(2+) 或 Cu(2+)。我们希望我们的方法在发展中地区有广泛的应用，用于监测某些地区的水质。
