Oral Defense Examination : Gold nanoparticle size, shape and charge determine the extent of nanoparticle induced endothelial leakiness effect

Speaker Wang Jinping (Supervisor: A/Prof Leong Tai Wei David)

Host Department of Chemical and Biomolecular Engineering

Date/Time 10 Oct - 10 Oct, 11.00am

Venue E5-02-32 , Faculty of Engineering, National University of Singapore


Nanoparticles could induce micron sized gaps between endothelial cells which we coined as nanoparticles induced endothelial leakiness (NanoEL) even without any tumor cells in the vicinity of the blood vessels cells; thus NanoEL is a novel nanoparticle driven effect distinct from the enhanced permeability and retention (EPR) effect. This presents an opportunistic window to control access of nanomedicine and drugs to tumors and other tissues without relying on the uncontrollable EPR effect. Nanoparticle parameters that determine NanoEL are slowly emerging but under intense investigation. In this work, it is proposed that size, shape and differences do play a role in determining the NanoEL effect. Au and mesoporous SiO2 based nanoparticles are used as model nanoparticles due to the high biocompatibility. We found that only certain size ranges (less than 300 nm) of spherical Au NPs can cause NanoEL by fitting into the adherens junctions between endothelial cells and disrupt the VE-Cadherin homophilic interactions. Moreover, the shapes of Au nanosphere, nanoflower and nanomultipods do not impact NanoEL significantly. Eventually, NanoEL effect may be a feasible and controllable manner for nanomedicines to access tumors easily.