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Updated: Jun 5, 2026

Single-Molecule Tracking Microscopy - A Tool for Determining the Diffusive States of Cytosolic Molecules
Published on: September 5, 2019
Mean square displacement analysis of single-particle trajectories with localization error: Brownian motion in an
1Department of Chemistry & Biochemistry, University of California at Los Angeles, 607 Charles E. Young Drive E., Los Angeles, California 90095, USA. michalet@chem.ucla.edu
Abstract:
We examine the capability of mean square displacement (MSD) analysis to extract reliable values of the diffusion coefficient D of a single particle undergoing Brownian motion in an isotropic medium in the presence of localization uncertainty. The theoretical results, supported by simulations, show that a simple unweighted least-squares fit of the MSD curve can provide the best estimate of D provided an optimal number of MSD points are used for the fit. We discuss the practical implications of these results for data analysis in single-particle tracking experiments.
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