比利时安特卫普大学Bals, Sara团队报道了液体环境下金纳米颗粒配体的直接可视化。相关研究成果发表在2024年6月27日出版的国际学术期刊《自然—化学》上。

金纳米颗粒、其表面配体和溶剂之间的相互作用对这些纳米颗粒的性质产生了至关重要的影响。尽管光谱和散射技术已被用于研究它们的系综结构，但在纳米尺度上全面理解这些过程仍然具有挑战性。电子显微镜可以表征局部结构和成分，但受到对比度不足、电子束灵敏度和超高真空条件要求的限制，这阻碍了对动力学方面的研究。

该文中，研究表明，通过开发高质量的石墨烯液体电池可以克服这些限制，研究液体环境中金纳米颗粒周围和配体-金界面的配体壳结构。使用这种石墨烯液体电池，研究人员可视化了金纳米棒表面配体分布的各向异性、组成和动力学。结果表明了表面活性剂组织的胶束模型。

该项工作提供了胶体纳米颗粒周围配体分布的可靠和直接的可视化。

附：英文原文

Title: Direct visualization of ligands on gold nanoparticles in a liquid environment

Author: Pedrazo-Tardajos, Adrin, Claes, Nathalie, Wang, Da, Snchez-Iglesias, Ana, Nandi, Proloy, Jenkinson, Kellie, De Meyer, Robin, Liz-Marzn, Luis M., Bals, Sara

Issue&Volume: 2024-06-27

Abstract: The interactions between gold nanoparticles, their surface ligands and the solvent critically influence the properties of these nanoparticles. Although spectroscopic and scattering techniques have been used to investigate their ensemble structure, a comprehensive understanding of these processes at the nanoscale remains challenging. Electron microscopy makes it possible to characterize the local structure and composition but is limited by insufficient contrast, electron beam sensitivity and the requirement for ultrahigh-vacuum conditions, which prevent the investigation of dynamic aspects. Here we show that, by exploiting high-quality graphene liquid cells, we can overcome these limitations and investigate the structure of the ligand shell around gold nanoparticles and at the ligand–gold interface in a liquid environment. Using this graphene liquid cell, we visualize the anisotropy, composition and dynamics of ligand distribution on gold nanorod surfaces. Our results indicate a micellar model for surfactant organization. This work provides a reliable and direct visualization of ligand distribution around colloidal nanoparticles.

DOI: 10.1038/s41557-024-01574-1

Source: https://www.nature.com/articles/s41557-024-01574-1