The innovation engine for new materials

Rachel Bae

Rachel Bae




University of California, Santa Barbara


Jonah Rosas

Faculty Sponsor(s): 

Angela Pitenis

Faculty Sponsor's Department(s): 


Project Title: 

Modeling Tissue Mechanics with Packed Granular Hydrogel Assemblies

Project Description: 

Recent studies have shown that the substrate on which cells are grown influences their morphology, proliferation, and migration. The mechanical properties of various in vivo substrates can reliably be modeled with hydrogels. In this study, we aim to create hydrogels with different mechanical properties representative of physiologically significant environments within the pancreas. Gels with a consistent diameter will help to determine how the mechanical forces of the cell’s environment affect cell behavior and disease progression without running the risk of cells engulfing smaller particles in the assembly. After polymerization,  acrylamide hydrogel particles are sized by Stokes sedimentation and analyzed by phase contrast microscopy to determine size distribution. Through microindentation on swollen gels, we have compared the mechanical properties of 3 wt% and 5 wt% polyacrylamide hydrogels. To characterize the rheological properties of our microgel assemblies, we will further analyze samples at 37 C with rheology to better understand the yield stress of these particle assemblies. The data establishes that increasing the rounds of sedimentation improves the yield of particles with a particular diameter, allowing us to make more homogenous gels for 3D printing applications and rheology.