Density of nanoparticles matters in nanobiotechnology

by David Tai Wei, LEONG
Density of nanoparticles matters in nanobiotechnology

The integrity of the vasculature system is intrinsically sensitive to biophysical cues. We have earlier found that certain nanomaterials could induce endothelial leakiness (nanoparticle induced endothelial leakiness). We now report that the density of the nanomaterial, a basic intrinsic material property not implicated in many nanoparticle-mediated biological effects, predominantly dictates the nanoEL effect. We demonstrated that the impinging force exerted by a library of increasing effective densities silica nanoparticles could directly increase endothelial permeability. The crossover effective particle density that induced nanoEL was between 1.57 g/cm3 to 1.72 g/cm3. A cumulative gravitational-mediated force of around 1.8 nN/μm along the boundaries of the vascular endothelial cadherin (VE-cad) adherens junctions appeared to be a critical threshold force required to perturb endothelial cell–cell adhesion. This resulted in the “snapping” of the mechanically pretensed VE-cad (Nanosnap), leading to the formation of micron-sized gaps that would dramatically increase endothelial leakiness.

This work has been published in ACS Nano on Mar 13, 2017 (doi: 10.1021/acsnano.6b07806)

Corresponding author(s): David Leong (
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