Fig. 7.

(A) Nano antenna for single-molecule surface enhanced Raman scattering (sm-SERS). The scale bar is 90 nm. The molecule can be trapped at the “hot spot” of the nano antenna and SERS signals can be enhanced via the directionality of the antenna to achieve single-molecule SERS detection. (B) Surface acoustic waves (SAW) based acoustic tweezers. Acoustic tweezers can manipulate single particles and cells in a biocompatible manner (top). SAW-based PCR utilizing photonic crystal to modulate SAWs for real-time PCR (bottom). The inset is electrophoretic gel analysis of the amplicon from the real-time PCR on SAW. (C) “DNA transistor” for next-generation genomic reader. A single-stranded DNA is passing through the nanopore under the influence of electric field. Bias voltages are applied through the nanopore structure to control the speed of ssDNA travelling inside nanopore. The precision of signal readout is expected to reach single-nucleotide level. (D) Schematic of the commercial “SMRT” cell product developed by Pacific Bioscience for DNA sequencing using ZMW technology. Images are reproduced from Ref. 76, 104, 106, 113, and 117.