FIG. 3.

Physical characterization of VLPs. (a) Electron microscopy was performed on purified samples and photographed at a magnification of ×60,000. The VLPs appear as uniformly shaped particles and are consistent with icosahedral symmetry. Estimates of particle size range from 18 to 25 nm by direct measurement. In the insert, the digitally magnified image (about fivefold) reveals fine structure and hexagonal symmetry of the VLP. (b) DLS analysis provided a means for estimating nanoparticle sizes in solution. DLS indicates that the solution contains particles ranging from monodisperse to small aggregates with an average diameter of 27.7 nm.