Hydrodynamic Radius of Polymer-Coated Nanoparticles Measured by Taylor Dispersion: A Mathematical Model.

This theoretical work addresses the characterization of polymer-coated nanoparticles via the analysis of Taylor dispersion experiments. Our focus is on determining the apparent hydrodynamic radius and the related accuracy bias, which results from polydispersity and optical-absorption-weighted averages. To that end, we construct a statistical model addressing joint distributions of particle core size and ligand surface density, which determine the hydrodynamic radius and optical absorption of such nanoparticles. Our model predicts that a polymer shell that is thick compared with the core radius results in a smaller bias than a thin shell, and the bias may become even negative when ligand surface density is sufficiently high.