Colorimetric response of peptide modified gold nanoparticles: An original assay for ultrasensitive silver detection
Colorimetric response of peptide modified gold nanoparticles: An original assay for ultrasensitive silver detection
复制标题
肽修饰金纳米粒子的比色响应：超灵敏银检测的原始测定
DOI：
10.1016/j.bios.2016.10.075
复制
发表时间：
2017-06-15
影响因子：
12.6
通讯作者：
Hu, Jiming
中科院分区：
文献类型：
--
作者：
Li, Xinyi;Wu, Zitong;Hu, Jiming
在本文中，我们首次提出了一种新颖的、超灵敏的检测Ag+离子的方法，利用这种方法，可以通过多肽与Ag+的相互作用来触发给定的多肽修饰的金纳米颗粒(多肽-AuNPs)的聚集。由于上述相互作用的机理尚未被研究过，因此该方法很少用于比色法测定银离子。在我们的实验中，对这种相互作用的原理进行了研究。此外，我们还将其应用于高灵敏度、高选择性的Ag+检测传感器的设计。正是Ag+诱导的多肽折叠结构导致了多肽-AuNPs的聚集。这种聚集是指Ag+与多肽中的α-氨基的氧键和氮键结合形成4配位的络合物。结果表明，银离子的选择性检测最低可达7.4 nm，线性范围为10-1000 nm。与其他方法相比，该方法具有简单、灵敏、稳定、省时等优点。此外，该生物传感器具有无干扰、现场快速检测等优点，在水样(如湖泊、自来水、饮用水等)的实际应用中表现出优异的性能。
In this article, we for the first time present an original and ultrasensitive assay to detect Ag+ ions, with which the aggregation of the given peptide-modified gold nanoparticles (peptide-AuNPs) can be triggered by the interaction between peptides and Ag+. The approach has rarely been used in the colorimetric determination of Ag+, because the mechanism of the above-mentioned interaction has not been studied through. In our assay, the principle of this interaction was investigated. Moreover, we applied it in the design of an extremely sensitive sensor for Ag+ detection with great selectivity. It is the Ag+-induced folding structure of the peptides that leads to the aggregation of peptide-AuNPs. The aggregation involves the formation of 4-coordinated complexes between Ag+ and peptides via bonding with the carbonyl oxygen and the nitrogen of the a-amino group in the peptides. The result shows that Ag+ ions can be selectively detected as low as 7.4 nM with a linear range of 10-1000 nM. Compared with other approaches, the proposed approach demonstrates superior simplicity, sensitivity, stability and time-saving. Furthermore, the biosensor excels in the practical application in water samples (e.g., lake, tap and drinking water) owing to its non-interference and on-site rapid determination.