Robust real-time 3D single-particle tracking using a dynamically moving laser spot.


Journal Article

Real-time three-dimensional (3D) single-particle tracking uses optical feedback to lock on to freely diffusing nanoscale fluorescent particles, permitting precise 3D localization and continuous spectroscopic interrogation. Here we describe a new method of real-time 3D single-particle tracking wherein a diffraction-limited laser spot is dynamically swept through the detection volume in three dimensions using a two-dimensional (2D) electro-optic deflector and a tunable acoustic gradient lens. This optimized method, called 3D dynamic photon localization tracking (3D-DyPLoT), enables high-speed real-time tracking of single silica-coated non-blinking quantum dots (∼30  nm diameter) with diffusive speeds exceeding 10  μm2 /s at count rates as low as 10 kHz, as well as YFP-labeled virus-like particles. The large effective detection area (1  μm×1  μm×4  μm) allows the system to easily pick up fast-moving particles, while still demonstrating high localization precision (σx =6.6  nm, σy =8.7  nm, and σz =15.6  nm). Overall, 3D-DyPLoT provides a fast and robust method for real-time 3D tracking of fast and lowly emitting particles, based on a single excitation and detection pathway, paving the way to more widespread application to relevant biological problems.

Full Text

Duke Authors

Cited Authors

  • Hou, S; Lang, X; Welsher, K

Published Date

  • June 2017

Published In

Volume / Issue

  • 42 / 12

Start / End Page

  • 2390 - 2393

PubMed ID

  • 28614318

Pubmed Central ID

  • 28614318

Electronic International Standard Serial Number (EISSN)

  • 1539-4794

International Standard Serial Number (ISSN)

  • 0146-9592

Digital Object Identifier (DOI)

  • 10.1364/ol.42.002390


  • eng