Figure 1.

General design of the microfluidic system. (a) Schematic drawing of a vessel with a yellow arrow indicating the direction of flow and a turquoise arrow indicating the transport across the endothelium. (b) Design of the microfluidic channel consisting of a glass coverslip as substrate and two parallel channels on top of each other separated by a polyethylene foil with a hole carrying an MPL-structured grid. An acrylic glass piece provides additional mechanical stability. (c) Sketch of the foil seeded with cells. The yellow arrows indicate flow along the channel and the turquoise arrow indicates diffusion of biomolecules and nanoparticles across the cell layer. This process is monitored using a high NA objective.