Zustiak’s primary research interests are in hydrogel biomaterials and tissue engineering, with emphasis on developing novel biomaterials as cell scaffolds and drug screening platforms, and elucidating matrix structure–property relationships as well as cell–matrix interactions. Biomaterial-based models are crucial for bridging the gap between traditional tissue culture and animal models by providing a cell environment that closely mimics real tissue. This research is highly multidisciplinary, merging the fields of engineering, materials science, and biology.