2D to 3D transformation of gold nanosheets on human adipose-derived α-elastin nanotemplates

Abstract

Controlling the morphology and surface properties of gold nanocrystals (AuNCs) can facilitate tailoring their localized surface plasmon resonance (LSPR) and surface-enhanced Raman scattering (SERS) properties for biomedical applications. However, the shape-controlled synthesis of AuNCs for bioapplications remains challenging, given its critical issues, such as the use of toxic reagents and multiple complicated steps. This study demonstrates the facile, biocompatible, and shape-controllable synthesis of AuNCs. This method employs human α-elastin (HαE) self-assemblies as a shape-directing template, reducing agent, and surfactant. Since HαE is a ubiquitous protein present in human tissue, it is non-toxic and non-immunogenic. This method is thus simple and biocompatible. Of particular note, the sheet-type HαE template enables the shape-controlled synthesis of AuNCs—gold nanoparticles, nanosheets, and a rose-flower-like nanostructure (AuRF) stacked with multiple nanosheets. Among the AuNCs, the AuRF exhibits unique optical and electromagnetic properties—an LSPR peak in the near-infrared (NIR) region and characteristic SERS peaks—given the rough surface with sharp edges. To the best of our knowledge, this is the first report on the biosynthesis of AuNCs using human-derived biomolecules such as HαE. The shape-controllable biosynthesis of AuNCs based on HαE may open up possibilities for a wide range of biomedical applications of AuNCs. © 2020 The Korean Society of Industrial and Engineering Chemistry