Facile Fabrication of Multi-targeted and Stable Biochemical SERS Sensors

The direct transfer of single- crystalline Au nanowires (NWs) onto Au substrates was achieved by a simple attachment and detachment process. In the presence of a lubricant, Au NWs grown vertically on a sapphire sub- strate were efficiently moved to an Au substrate through van der Waals inter- actions. We demonstrate that the trans- ferred Au NWs on the Au substrate can act as sensitive, reproducible, and long-term-stable surface-enhanced Raman scattering (SERS) sensors by detecting human a-thrombin as well as Pb 2 + and Hg 2 + ions. These three bio- chemically and/or environmentally im- portant analytes were successfully de- tected with high sensitivity and selec- tivity by Au NW-SERS sensors bound by a thrombin-binding aptamer. Fur- thermore, the as-prepared sensors re- mained in working order after being stored under ambient conditions at room temperature for 80 days. Because Au NWs can be routinely transferred onto Au substrates and because the re- sultant Au NW-SERS sensors are highly stable and provide with high sensitivity and reproducibility of detec- tion, these sensors hold potential for practical use in biochemical sensing.