Ordered silicon nanocones arrays for label-free DNA quantitative analysis by surface-enhanced Raman spectroscopy

Ordered vertical silicon nanocones arrays coated with silver nanoparticies (AgNPs@SiNCs) arc developed as surface-enhanced Raman scattering (SERS)-active substrate, which features good uniformity and reliable reproducibility of SERS signals, Label-free DNA at low concentrations (10(-8) M) could be quantitatively analyzed via SERS using the AgNPs@SiNCs. The Raman peak at 732 cm(-1) due to adenine breathing mode was selected as an endogenous Raman marker for quantitative detection of label-free DNA. The AgNPs@SiNCs as high-performance SERS-active substrates are attractive for surface enhancement mechanism investigation and biochemical sensing applications. (C) 2011 American Institute of Physics. [doi:10.1063/1.3650937]