Fig. 13. Plasmonic trapping of biomolecules.

a Schematic of plasmonic trapping of a biomolecule in a double nanohole. b Scanning electron microscopy image of the double nanohole used in the protein binding and control experiments. c Time traces of the optical power transmitted through the double nanohole with a BSA solution in PBS buffer with pH = 7.4 at an incident optical power of 13.4 mW. d Trapping of a DNA molecule by a plasmonic tweezer system combining a gold bowtie and a nanopore, where its nucleotide sequence could be deciphered through deconvolution of the SERS signals that uniquely identify each of the four DNA nucleotides. e Schematic illustration of plasmonic tweezers for DNA. a–c Reproduced with permission from ref. ¹¹², Copyright 2011 American Chemical Society. d Reproduced with permission from ref. ²⁴⁹, Copyright 2015 American Chemical Society. e Reproduced with permission from ref. ²¹⁵, Copyright 2013 American Chemical Society