Design and One-Pot Synthesis of Capsid-like Gold Colloids with Tunable Surface Roughness and Their Enhanced Sensing and Catalytic Performances

• Published in: ACS applied materials & interfaces 2020-11, Vol.12 (44), p.50152-50160
• Main Authors: Lin, Guanhua, Xian, Longbin, Zhou, Xuemao, Wang, Shuo, Shah, Zameer Hussain, Edwards, Scott A, Gao, Yongxiang
• Format: Article
• Language: English
• Subjects: Biomimetic Materials - chemical synthesis; Biomimetic Materials - chemistry; Catalysis; Colloids - chemical synthesis; Colloids - chemistry; Gold - chemistry; Molecular Structure; Particle Size; Spectrum Analysis, Raman; Surface Properties; Surfaces, Interfaces, and Applications
• ISSN: 1944-8244; 1944-8252
• DOI: 10.1021/acsami.0c14802

Viral capsid-like particles tiled with mosaic patches have attracted great attention as they imitate nature’s design to achieve advanced material properties and functions. Here, we develop a facile one-pot soft-template method to synthesize biomimetic gold capsid-like colloids with tunable particle size and surface roughness. Uniform submicron-to-micron-sized hollow gold colloidal particles are successfully achieved by using tannic acids as soft templates and reducing agents, which first self-assemble into spherical complex templates before the reduction of Au3+ ions via their surface hydroxyl groups. The surface roughness, the size, and the total number of the patches of the prepared gold particles are further tuned, utilizing a mechanism that offers morphology control by varying the number of surface hydroxyl groups participating in the reduction reactions. Among different capsid-like gold colloids, those possessing a rough surface display superior catalytic properties and show promising results as surface-enhanced Raman spectroscopy (SERS) solid substrates for detecting small organic molecules and biomimetic enzymes in a liquid phase for sensing biomolecules in real samples. These capsid-like gold colloids are also expected to find practical applications in delivery systems, electronics, and optics. We believe that our strategy of imitating nature’s design of capsid-like structures should also be used in the design and fabrication of other functional colloidal particles.