Nano-gap electrode dielectrophoresis for tether-free trapping and interferometric-scattering detection of single 20 nm particles

Jacco Ton, Théo Travers, Jamal Soltani, Daniel Wijnperle, Dmytro Shavlovskyi, Michel Orrit, Sergii Pud

Research output: Working paperPreprintAcademic

94 Downloads (Pure)

Abstract

Accurate detection and characterization of nanoparticles within confined spaces is crucial for applications ranging from nanofluidics to biotechnology. We present a novel approach that combines interferometric scattering (iSCAT) detection with trapping by dielectrophoresis (DEP) to achieve label-free detection of nanoparticles that are trapped and/or actuated between nano-gap electrodes. DEP utilizes the interaction between the induced dipole of the particle and the applied electric field to create a trapping potential. We demonstrate our method by trapping and label-free detection of down to 20 nm polystyrene nanoparticles. Additionally, we demonstrate that the signal-to-noise ratio of our detection can be boosted up to 20-fold by periodic actuation of the nanoparticle in the trap. This is done by a digital lock-in detection scheme on the modulated scattering signal. Our method holds promise for various applications, including assembly of nanoparticles, single-particle property analysis, and nanofluidic devices.
Original languageEnglish
PublisherArXiv.org
Number of pages69
DOIs
Publication statusPublished - 20 May 2024

Keywords

  • physics.optics
  • physics.chem-ph

Fingerprint

Dive into the research topics of 'Nano-gap electrode dielectrophoresis for tether-free trapping and interferometric-scattering detection of single 20 nm particles'. Together they form a unique fingerprint.

Cite this