Relevance of two-dimensional Brownian motion dynamics in applying nanoparticle tracking analysis.

Nanoparticle Tracking Analysis (NTA) is an image analysis-based technique that deduces the particle size from the changing position of scattering diffusing particles in a sequence of images. It is shown that a basic understanding of the underlying physical principles largely helps to prevent artifacts. In fact, an inappropriate selection of both software parameters, such as maximum particle jump or minimum track length, as well as sample preparation aspects (such as degree of dilution) may give rise to inaccurate or even erroneous results.