Ordered gold nanoparticle arrays on the tip of silver wrinkled structures for single molecule detection

We demonstrate a method for fabricating nanoparticles in a line at the top of silver wrinkled structures by tilting the substrate. The center of gravity of the colloidal droplets was moved backward, resulting in a small volume of droplets at the front of the colloidal droplet. The droplet rapidly evaporated, and the nanoparticles that remained formed lines of highly ordered nanoparticles. The distance between the nanoparticles changed after stretching the PDMS substrate due to the Poisson effect. An optimal plasma effect was achieved by controlling the distance between the nanoparticles. Finally, the Surface-Enhanced Raman Scattering (SERS) effects of CV and R6G molecules in water were determined, and the detection limit was 10−20 M. This method provides an extremely high sensitivity SERS substrate for the detection of biomolecules.