Interaction of cells with patterned reactors.

Surface coatings that allow externally controlled interaction with cells are of interested for diverse biomedical applications. We fabricated particle patterns and assessed the interaction of these substrates with endothelial cells and hepatocytes. The particles were turned into subcompartmentalized reactors by immobilizing glucose oxidase loaded liposomes sandwiched between polymer layers. The reactor activities depending on the number of liposome deposition steps were confirmed in solution and on patterned surfaces. Finally, reduced viability of hepatocytes adhering to the reactor patterned surfaces in the presence of glucose was observed due to the local production of hydrogen peroxide. This first report on patterned reactors in combination with cells opens up vast opportunities to assemble interactive nanobiointerfaces.

Mucopenetrating micelles with a PEG corona.

Crossing the intestinal mucus layer is a long-standing challenge for orally delivered nanoparticles carrying therapeutic cargo. We report the assembly of mucopenetrating cargo-loaded micelles using block copolymers consisting of either linear poly(ethylene glycol) (PEG) or bottle-brush poly(oligo(ethylene glycol)methacrylate) (PEGb) as the hydrophilic block and poly(caprolactone) (PCL) or poly(cholesteryl methacrylate) (PCMA) as the hydrophobic extension. The micelles were shown to preserve their stability and retain ∼50% of their cargo in simulated gastric fluid. The ability of micelles to diffuse through reconstituted porcine mucus was assessed in a microfluidic set-up. Finally, the delivery of Nile Red as a hydrophobic model cargo across a mucus layer produced by epithelial cells was demonstrated. These engineered mucopenetrating micelles have potential to be developed into efficient absorption enhancers, contributing a nanotechnology solution to oral drug delivery.