The results of this study have been published in Advanced Science.

Gold nanostructures play a critical role in biosensing applications but have faced sensitivity limitations due to ohmic and radiative losses in metal. The strategic arrangement of gold nanostructures into 2D ncp arrays can reduces radiative loss, supporting a plasmonic surface lattice resonance (SLR) property with a remarkable two-orders-of-magnitude increase in sensitivity theoretically.

In this research, scientists revealed a mechanism termed self-confined solid-state dewetting, which completely changes nanofabrication techniques for wafer-scale patterning of ncp gold nanoparticle arrays. By combining this method with a soft lithography process, they have solved the problem of reproducibility associated with colloidal crystal self-assembly, which was difficult before.

This new method allows them to easily fabricate the batch of ncp gold arrays with consistent ordering and optical properties. These nanoparticle arrays show strong SLR properties that are useful for sensing tiny molecules when they are excited by light. This advancement, which achieves sensitive plasmonic sensing of molecular interactions using a simple transmission setup, could lead to better portable devices for detecting small amounts of substances.

"We anticipate this work could open a door for sensitive SLR biosensing applications and shed light on portable commercialization," said Dr. LIU Dilong, member of the team.

Figure 1: Illustrates the self-confined solid-state dewetting of gold nanoshells deposited on a spherical surface. (Image by LIU Dilong) 

Figure 2: Demonstrates reproducible patterning of ncp gold nanoparticle arrays through a soft lithography process. (Image by LIU Dilong)  

Figure 3: Explores plasmonic SLR sensing of molecular interactions based on a transmission setup. (Image by LIU Dilong)