Hierarchical self-assembly of random mica nanosheet-stabilized silver nanoparticles into flower microstructures for highly sensitive SERS substrates

Abstract

In this study, we observed the formation of flower-like microstructures by the hierarchical self-assembly of random mica nanosheet (RMN)-stabilized silver nanoparticles (AgNPs) without organic stabilizers. The SERS spectra of adenine molecules from DNA were measured as functions of the AgNP sizes and microstructures with substrates formed using various RMN/AgNP precursor ratios. The AgNP@RMN substrates significantly contributed to the high SERS sensitivity to adenine molecules with a SERS enhancement factor (EF) of 1.5 × 10⁵. These novel AgNP@RMN hybrid microstructures can be utilized as SERS substrates for biological sensing applications.