Nanoparticles (NPs) have been widely investigated in
the nanomedicine
field. One of the main challenges is to accurately predict the NP
distribution and fate after administration. Microfluidic platforms
acquired huge importance as tools to model thein vivoenvironment. In this study, we leveraged a microfluidic platform
to produce FITC-labeled poly(lactide-co-glycolide)-block-poly(ethylene glycol) (PLGA-PEG) NPs with defined
sizes of 30, 50, and 70 nm. The study aimed to compare the ability
of NPs with differences of 20 nm in size to cross an endothelial barrier
using static (Transwell inserts) and dynamic (microfluidic perfusion
device)in vitromodels. Our results evidence a size-dependent
NP crossing in both models (30 > 50 > 70 nm) and highlight the
bias
deriving from the static model, which does not involve shear stresses.
The permeation of each NP size was significantly higher in the static
system than in the dynamic model at the earliest stages. However,
it gradually decreased to levels comparable with those of the dynamic
model. Overall, this work highlights clear differences in NP distribution
over time in static versus dynamic conditions and distinct size-dependent
patterns. These findings reinforce the need for accuratein
vitroscreening models that allow for more accurate predictions
ofin vivoperformance.