Number of publications on nanowire, nanotube or nanopillar for 1996?2015 (Source, ISI).

 (a) Schematic representation of the experimental set-up for synthesizing single-crystalline Au NWs. (b) Scanning electron microscope (SEM) and molecular dynamics (MD) images showing the vertical (enclosed by red dotted line) or horizontal growth process of Au NWs. Scale bars in (ii?vi) are 100 nm. (c) 45°

  tilted SEM image of vertically grown Au NWs. (d) Transmission electron microscope (TEM, left) and high-resolution TEM (middle) images and selected area electron diffraction pattern (right) of a Au NW. Reproduced from ref.[25].

 (a) SEM images taken during the tensile deformation of a Au NW. Reproduced from ref. [26]. Scale bar is 1 μ

 m. (b) Stress-strain curve of a Au NW under tensile stress. Reproduced from ref. [26]. (c) SEM images showing U-shape bending and complete recovery of a Au NW while pushed against and withdrawn from a solid surface. Reproduced from ref.[29].

 I-V curve measured from a single Au NW. Inset shows the SEM image of four-probe Au NW device for I-V measurement. Reproduced from ref. [29].

 (a) Schematic representation and optical images showing the process of fabricating a Au NW electrode. (b) CV of a Au NW electrode measured in a 50 mmol/L sulfuric acid solution at a scan rate of 50 mV/s. (c) CV of a Au NW electrode in a 20 mmol/L K3Fe(CN)6 solution without supporting electrolyte at a scan rate of 200 mV/s. (d) The electrical impedances of Au NW electrodes (n = 7) measured at 1 kHz. The error bar (magenta line) represents standard deviation. Reproduced from ref. [32].

 (a) Schematic representation of electrically triggered gene delivery into the nucleus of a living cell using a Au NW nanoinjector. (b) Schematic representation of the experimental set-up for Au NW nanoinjector-based intracellular delivery system. (c) Optical images showing the insertion of a Au NW nanoinjector into cytoplasm (c-i) and nucleus (c-ii). (d) Optical images showing the flexible insertion of a Au NW nanoinjector (from d-i to d-ii). Reproduced from ref.[32].

 (a) Optical (left) and fluorescence (right) images of the Au NW on which fluorescent dye-intercalated DNA is attached. (b) Fluorescence images of Au NWs where fluorescent dye-labeled DNA is firstly attached and then detached by electric pulses of different potential and duration as written in the images. (c) Fluorescence intensities remaining on the Au NW nanoinjectors after detaching fluorescent dye-intercalated DNA by electric pulses of different potential and duration. Reproduced from ref.[32].

 (a) Fluorescence (a-i) and merged fluorescence/optical (a-ii) images of the cell into which GFP-coding plasmid was delivered. (b) Fluorescence (b-i) and merged fluorescence/optical (b-ii) images of the cell into which GFP-coding linear DNA was delivered. Reproduced from ref.[32].