Figure 4.

Particles with coatings that prevent nonspecific binding like PEG have greater tumor accumulation and less RES organ accumulation than particles that have been opsonized. Smaller‐sized nanoparticles tend to have greater tumor perfusion whereas larger particles tend to remain at the periphery near the vessel. This is due to the greater diffusivity of smaller particles through tissues. Particles with greater aspect ratios are seen to have higher tumor accumulation than more spherical‐shaped counterparts. The enhancement is believed to be a result of having greater diffusivity within tissues and having greater margination toward the vessel walls when in circulation