Size-Defined Cracked Vesicle Formation via Self-Assembly of Gold Nanoparticles Covered with Carboxylic Acid-Terminated Surface Ligands

作者：Wei, Jinjian; Mitomo, Hideyuki^*; Tani, Takeharu; Matsuo, Yasutaka; Niikura, Kenichi; Naya, Masayuki; Ijiro, Kuniharu^*

来源：Langmuir, 2018, 34(41): 12445-12451.

DOI：10.1021/acs.langmuir.8b02966

• PLASMON RULER EQUATION
• FUNCTIONAL MATERIALS
• METAL NANOPARTICLES
• NANOSTRUCTURES
• COLLOIDOSOMES
• NANOVESICLES
• NANOCRYSTALS
• DEPENDENCE
• CLUSTERS
• THERAPY

The self-assembly of gold nanoparticles (GNPs) into a defined structure, particularly hollow capsule structures, provides great potential for applications in materials science and medicine. However, the complexity of the parameters for the preparation of those structures through self-assembly has limited access to critical mechanistic questions. With this in mind, we have studied GNP vesicle (GNV) formation through self-assembly by the surface modification of GNPs with low-molecular-weight ligands. Here, we successfully prepared GNVs composed of GNPs with a diameter of 30 nm by surface modification with carboxylic acid-terminated fluorinated oligo(ethylene glycol) ligands (CFLs). As the carboxylic acid has two states (protonated and deprotonated), the balance of the attraction and repulsion between GNPs covered with CFLs is tunable. Sodium carboxylate-terminated fluorinated oligo(ethylene glycol) ligands (SCFLs) provided smaller GNVs than did CFLs at 0.8 X 10(11) NPs/mL. Time-course study revealed that CFL-covered GNPs quickly form small aggregates and gradually grow to larger GNVs (ca. 200 nm), but no gradual growth was observed for SCFL-covered GNPs. This result indicated that the electrostatic repulsion inhibits fusion of the small GNVs. The size of the GNVs formed with the aid of CFLs was independent of the initial GNP concentration, but the extinction spectra were concentration-dependent. Electron microscopy imaging and simulations supported the defect formation in the assemblies. These results provided new insights into the vesicle formation mechanism.

• 出版日期2018-10-16
• 单位山东师范大学