(162ai) Porous and Ultrasoft Membranes for Biomicroreactors with Modulated Stiffness Enabled By Soft Dendritic Colloid Nonwovens

We will report how porous, elastic, cell scaffolds with morphological features similar to that of the branched, fibrous architectures comprising physiological tissues to culture human epithelial lung cells and investigate cellular response to aerosolized nanomaterials. The scaffolds are made from biocompatible polyurethane soft dendritic colloid (SDC) particulates. SDCs are a new class of polymeric material characterized by a branched corona of nanofibers spread out in all directions and produced in a scalable polymer precipitation process under intensive shear.^[1] Their characteristic, hierarchical structure enables remarkable adhesion and interparticle networking properties, mimicking the contact splitting effect seen in gecko leg adhesion. SDC membranes are ultrasoft with controllable moduli of physiological softness (< 1 MPa) that can mimic both soft, healthy tissue and stiffened, diseased tissues characterized by stiffened fibers resulting from pathologies such as cystic fibrosis. We utilize these membranes as tissue matrix surrogates and used to probe the A549 epithelial lunge cell model cellular response to aerosolized CON and Ta Au nanoparticles on highly fibrous and porous 3D substrates of differing stiffness as well as stiff and 2D Transwell culture conditions. Finally, we will present a system to cyclically actuate the using a 3D printed and magnetic silicone ink to mimic the respiration process with in vitro models. We will also discuss the remarkable versatility granted by the shear-driven polymer precipitation process to produce nanofibrous SDCs from a number of biomaterials and the facile production of a new class of nonwoven and aerogel SDC scaffolds.