Jump to main content
Jump to site search

Issue 44, 2019
Previous Article Next Article

Opto-thermophoretic separation and trapping of plasmonic nanoparticles

Author affiliations


Optical tweezers are powerful tools to trap, transport, and analyse individual nano-objects at dilute concentrations. However, it is still challenging to manipulate isolated single nano-objects in dense target environments with various kinds of materials, such as in living cells and mixtures of nanocolloids. In the present work, we have succeeded in the selective trapping of a few gold nanoshells with specific sizes and sweeping others out completely, only by irradiating the dense colloidal suspension of gold nanoshells with a focused near infrared continuous-wave (CW) laser. This was achieved by an interplay between optical gradient- and thermophoretic forces: while the gradient force traps the targets at the focal spot, the thermophoretic force pushes others out from the focal spot. The distance between the trapped targets and the separated others was longer than 20 μm, allowing us to measure plasmonic scattering spectra of the trapped targets at a single-nanoparticle level. The present method paves a way for manipulating and analysing single nano-objects in dense mixtures of targets and various kinds of materials.

Graphical abstract: Opto-thermophoretic separation and trapping of plasmonic nanoparticles

Back to tab navigation

Supplementary files

Article information

14 Jun 2019
02 Aug 2019
First published
05 Aug 2019

Nanoscale, 2019,11, 21093-21102
Article type

Opto-thermophoretic separation and trapping of plasmonic nanoparticles

K. Setoura, T. Tsuji, S. Ito, S. Kawano and H. Miyasaka, Nanoscale, 2019, 11, 21093
DOI: 10.1039/C9NR05052C

Social activity

Search articles by author