Gold nanoparticle layer: a versatile nanostructured platform for biomedical applications

Abstract

Gold nanoparticle layers (GNPLs) refer to a kind of nanostructured surfaces with immobilized gold nanoparticles (GNPs) at high density on a substrate. These materials not only exhibit excellent properties similar to those of free GNPs, such as good biocompatibility, large surface area, high electron transfer capability, unique photothermal properties, and convenient chemical and biological modification, but also have unique two-dimensional surface topography, making them suitable as nanostructured platforms. These properties account for the increasing applications of GNPLs in biology and medical science in recent years. In this review, we first briefly introduce several fabrication methods for GNPLs, including electrodeposition, chemical plating, spin coating, layer-by-layer deposition and patterned GNPLs. We then discuss biological applications of GNPLs, including in surface enhanced Raman scattering (SERS)- and enzyme linked immunosorbent assay (ELISA)-based bioassays, as electrodes modified with GNPLs for electrochemical biosensing, and as platforms for investigation of the interactions between cells and nanostructured surfaces. Surfaces with photothermal effects based on GNPLs for intracellular macromolecule delivery and antibacterial applications are also discussed. Finally, several challenges regarding research on GNPLs are presented, such as the development of fabrication methods that are capable of precisely controlling the hierarchical structure and further investigation of the influence of the roughness/topography on cellular behavior. It is our hope that through this review, researchers may gain a deeper understanding of GNPLs and become involved in their investigation.