Hydrophobic Plasmonic Nanoacorn Array for a Label-Free and Uniform SERS-Based Biomolecular Assay

• DOI: 10.1021/acsami.0c03993
• Publication Date: 2020-06-08T14:31:49Z
• Authors: Kai Zhu; Zhuyuan Wang; Shenfei Zong; Yun Liu; Kuo Yang; Na Li; Zhile Wang; Lang Li; Hailong Tang; Yiping Cui
• Keywords: Aptamer

A surface-enhanced Raman scattering (SERS) aptasensor based on a hydrophobic assembled nanoacorn (HANA) was developed with improved reproducibility and reduced nonspecific binding effect. In the fabrication process, hexagonal-packed gold film over nanosphere (AuFON) arrays first obtained used as plasmonic substrate. Then, uniform sub-3 nm molecular spacer array (containing reporters) prepared by patterning nanometric hydrophilic ultrathin patches onto AuFON, in which thin layer is composed of polymers aptamers. During sensing HANA smartly impedes adsorption SERS probes Au@Ag nanocubes (Au@Ag NCs) absence targets. presence targets, displacement aptamers occurs due to specific interaction between targets aptamers, NCs can be AuFON through electrostatic interactions polymers. Thus, signals reporter molecules inside dramatically enhanced formation nanoparticle-on-mirror (NPoM) array. such aptasensor, well-ordered distribution ensures excellent repeatability, while precise subnanometer junctions guarantee high sensitivity. More importantly, since surface greatly reduce adsorption, tedious process blocking that employed traditional biosensors no longer needed. Using platform, human epidermal growth factor receptor 2 (HER2) three exosomal proteins were analyzed sensitivity good (RSD < 7%) whole-blood samples.