标题：Self-Assembled Templates of Aromatic Pentapeptides for Synthesis of CdS Quantum-Dots to Detect the Trace Amounts of Hg2+ in Aqueous Solutions
作者：Meng, Min; Dou, Yingying; Xu, Wenlong; Hao, Jingcheng
作者机构：[Hao, Jingcheng] Shandong Univ, Key Lab Colloid & Interface Chem, Minist Educ, Jinan 250100, Peoples R China.; [Hao, Jingcheng] Shandong Univ, Key L 更多
会议名称：6th Asian Conference on Colloid and Interface Science (ACCIS)
会议日期：NOV 24-27, 2015
来源：JOURNAL OF OLEO SCIENCE
关键词：self-assembly; templating synthesis; aromatic pentapeptides; CdS quantum; dots; trace detecting
摘要：Molecular self-assembly has become a popular tool to prepare nanomaterials with potential applications, such as ion-responsive detection of He2+ in aqueous solutions. In this study, FFACD aromatic pentapeptides, whose N-terminuses were protected by carboxyl (Ac-FFACD) or a 9-fluorenylmethoxycarbonyl group (Fmoc-FFACD), were chosen as building blocks to produce nanostructures in solutions. Based on the preliminary determination of the critical aggregation concentration (CAC) of Ac-FFACD and Fmoc-FFACD aromatic pentapeptides in water, the order of magnitude of which is 10(-5) mol.L-1, self-assembled spiral and networked nanowires can be easily obtained over a range of concentrations. These nanowires were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM). The self-assembled spiral and networked nanowires were designed to be used as templates for preparing CdS quantum dots (QDs) in-situ at room temperature. The peptide-functionalized, nanowire-encapsulated CdS QDs can be used for rapid, sensitive, and selective detection of trace amounts of mercuric ions (Hg2+) in aqueous solutions. This method enables rapid, linear detection (the linear correlation coefficients are 0.9972 of Delta F = 257.09 + 3.58 c(Hg)(2+) for Ac-FFACD and 0.9994 of Delta F = 48.13 + 32.96 c(Hg)(2+) for Fmoc-FFACD) with the Hg2+ limit of detection at 300.85 ng.L-1 and 32.09 ng.L-1 for Ac-FFACD and Fmoc-FFACD, respectively. The supramolecular, self-assembled nanowires, fabricated from the two aromatic pentapeptides and having encapsulated QDs, exhibit superior properties attributable to the large loading capacity and the coordination sites of these peptides with Hg2+. These structures can serve as novel He2+ sensors and have possible applications for detection of various targets in scientific and engineering systems.