Trapping analyte molecules in hotspots with modified free-standing silver bowtie nanostructures for SERS detection

Abstract

In this paper, we present a method to trap analyte molecules in hotspots by fabricating free-standing silver bowtie nanostructures with supporting bridges. The existence of supporting bridges makes more analyte molecules in hotspots, which efficiently enhance the Raman intensity. An enhancement factor of 2.4 × 10⁸ is obtained for the structures, and a low concentration of analyte (10⁻¹⁰ M) can be detected. Furthermore, the relative standard deviation for Raman measurement is down to 5.91% for the structures. This method may be applied for SERS measurements.