Institute of Chemistry and The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel; The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
The Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
J Colloid Interface Sci. 2023 Feb;631(Pt A):66-76. doi: 10.1016/j.jcis.2022.10.154. Epub 2022 Nov 2.
We present a short peptide of only six amino acids that can be used in ambient conditions to simultaneously reduce either Au or Ag ions, forming nanoparticles, and function as a stabilizing capping agent. At acidic pH, Hg ions oxidize the silver nanoparticles and Fe ions promote the aggregation of the gold nanoparticles. At alkaline conditions, Mn ions induce the aggregation of the silver nanoparticles. Through the absorbance changes of these processes, these peptide-capped nanoparticles demonstrated a fast, selective, and sensitive pH-dependent detection system. The limit of detection of Hg, Mn, and Fe was 319 nм, 184 nм, and 320 nм, respectively. Furthermore, the formed gold nanoparticles were successfully enveloped by a silver shell in a peptide-mediated photoreduction process. These bimetallic Au@Ag core/shell nanoparticles were characterized using UV-vis spectroscopy, high-resolution scanning transmission electron microscopy (HR-STEM), and energy dispersive X-ray spectroscopy (EDS). While prior studies used peptides as ligands for nanoparticles, the versatile abilities of the novel peptide presented in this study display the promising potential of using peptides for nanoparticles synthesis. This is because a single peptide can be used in a single-step one-pot synthesis to prepare and stabilize AuNPs, AgNPs, and Au@Ag core/shell nanoparticles, while also allowing to selectively probe different metal ions.
我们提出了一个只有六个氨基酸的短肽，可在环境条件下同时还原金或银离子，形成纳米颗粒，并作为稳定的封端剂。在酸性 pH 值下，汞离子氧化银纳米颗粒，铁离子促进金纳米颗粒的聚集。在碱性条件下，锰离子诱导银纳米颗粒的聚集。通过这些过程的吸光度变化，这些肽封端的纳米颗粒展示了一种快速、选择性和灵敏的 pH 依赖的检测系统。Hg、Mn 和 Fe 的检测限分别为 319、184 和 320nm。此外，在肽介导的光还原过程中，形成的金纳米颗粒成功地被银壳包裹。通过紫外可见光谱、高分辨率扫描透射电子显微镜（HR-STEM）和能谱（EDS）对这些双金属 Au@Ag 核/壳纳米颗粒进行了表征。虽然之前的研究使用肽作为纳米颗粒的配体，但本研究中提出的新型肽的多功能能力显示了使用肽合成纳米颗粒的巨大潜力。这是因为单个肽可以在一步一锅合成中用于制备和稳定 AuNPs、AgNPs 和 Au@Ag 核/壳纳米颗粒，同时还允许选择性地探测不同的金属离子。
