One-step fabrication of sub-10-nm plasmonic nanogaps for reliable SERS sensing of microorganisms.

摘要: Abstract Nanoscale gaps in noble metal films can produce intense electromagnetic enhancement. When Raman-active molecules are positioned these regions, their surface-enhanced Raman scattering (SERS) signals be dramatically enhanced. However, the lack of convenient and reliable fabrication methods with ultrasmall nanogaps ( 3 times compared to continuous Ag film a smooth surface (the roughness is 0.5 nm) without nanogaps. Since there no chemicals used during fabrication, this substrate has clean surface, which crucial for acquiring SERS spectra. This SERS-active then been applied identify series microorganisms, excellent, reproducible spectra were obtained. Finally, set piecewise-linear equations provided according correlation between intensity rhodamine 6G (R6G) concentration, detection limit calculated 0.2×10 −8  M. These results suggest that high pressure sputtering an technique fabricating sub-10-nm plasmonic nanogaps, SERS-based methodology very promising being biological sensing field.