Size‐tunable two‐dimensional Pd@Au nanoplates as a platform for fluorescence sensing

Abstract

Two‐dimensional (2D) nanomaterials have been widely used as novel biosensing platforms, but it is still a challenge to synthesize such materials with controlled shape, composition, and structure for further application in analytical sensing devices. In this work, through a seeded regrowth method, uniform hexagonal Pd@Au nanoplates with well‐defined thicknesses and tunable sizes were synthesized. The Pd@Au nanoplates showed strong absorption in the visible and near‐infrared spectral range, which contributed to their high fluorescence quenching ability. In particular, the Pd@Au nanoplates exhibited different affinities toward single‐stranded DNA (ssDNA) and double‐stranded DNA (dsDNA). As a proof of concept, Pd@Au nanoplates were applied for the first time as a highly efficient fluorescent sensing platform for the rapid, sensitive, and selective detection of DNA and small molecules. This work further provides an avenue for understanding the interaction between 2D nanomaterials and biomolecules, which will definitely stimulate more interest in designing novel sensing platforms for extending the applications of nanomaterials in bioanalysis.