Laser-induced convection shifts size distributions in Nanoparticle Tracking Analysis

Wil H Hoffmann, Niall Mulkerns, Simon R Hall, Henkjan Gersen*

*Corresponding author for this work

Research output: Contribution to journalArticle (Academic Journal)peer-review

1 Citation (Scopus)
32 Downloads (Pure)


This work discusses the effects of increasing laser power on the size data derived from NTA for particles of known size and scatterers in solutions of flufenamic acid in ethanol. We find that whilst a higher laser power reveals more particles as expected, their residence time changes due to laser-induced convection. This reduced residence time decreases the number of tracks available for individual particle size determination, shifting the size distribution to smaller values. This problem is overcome by using a shutter to inhibit the development of convection currents, increasing particle residence time and reducing the error on the size distribution. The detailed understanding of laser-induced convection permits more robust size characterisation of mesoscopic organic clusters, which play a key role in two-step nucleation theory.
Original languageEnglish
Pages (from-to)5694 - 5702
Number of pages9
JournalNanoscale Advances
Issue number19
Early online date1 Sep 2021
Publication statusPublished - 7 Oct 2021

Bibliographical note

Funding Information:
W. H. H., S. R. H., and H. G. acknowledge the Engineering and Physical Sciences Research Council (EPSRC) for funding under grant number EP/L016648/1. W. H. H. and S. R. H. acknowledge support by MagnaPharm, a European Union Horizon 2020 Research and Innovation programme under grant agreement number 736899. N. M. and H. G. acknowledge support from an EPSRC National Productivity Investment Fund cofunded by Carbometrics under grant number EP/R51245/X. W. H. H. thanks Adrian Crimp and his team at the University of Bristol Mechanical Workshop for machining components of the device.

Publisher Copyright:
© The Royal Society of Chemistry.


  • Nanoparticle detection
  • Brownian motion
  • convection
  • light scattering
  • mesoscopic cluster
  • nanoparticle tracking analysis


Dive into the research topics of 'Laser-induced convection shifts size distributions in Nanoparticle Tracking Analysis'. Together they form a unique fingerprint.

Cite this