Measuring the hydrodynamic size of nanoparticles in aqueous media using batch-mode dynamic light scattering.

Particle size characterization is of particular importance to nanomedicine. The size similarity of nanoparticles to biological moieties is believed to impart many of their unique medical properties. Here we present a method for sample preparation and the determination of mean nanoparticle size (hydrodynamic diameter) using batch-mode dynamic light scattering (DLS) in dilute aqueous suspensions. We then demonstrate this method for 30 nm colloidal gold.