Optimization of 3D-printed microstructures for investigating the properties of the mucus biobarrier

In order to overcome the mucus biobarrier for drug delivery purposes, a better understanding of the interactions between mucus and the drug carrier is needed. We propose optical catapulting of 3D-printed microstructures with tailored shape and surface chemistry as a means to study the interaction filtering properties of a model mucus biobarrier in dynamic conditions. Using twophoton polymerization, we fabricate microstructures with a resolution of approximately 200 nm. We introduce amino functional groups on the surface of the IP-L 780-derived polymer in a single step process via UV-assisted functionalization with an anthraquinone amine photolinker. Our optical catapulting system relies on Generalized Phase Contrast for beam shaping and it allows us to manipulate microstructures over a distance of 250 µm, similar to the mucus layer thickness in the upper part of the lower human intestine. This work is part of an ongoing endeavor to establish Light Robotics as a valuable toolbox for biomedical research.