What happens when we infuse cells and biological tissues with human-made materials? The possibilities are endless; we open up a new world for interacting with our cells, from measuring minuscule signals within tissues to changing how they behave and respond to various situations. One popular approach to inserting these materials is to build them within the tissues themselves. Polymers are a special type of material that consist of chains of repeating subunits known as monomers. They can be assembled at a site of interest in a tissue, which allows us to build networks throughout cells or choose specific parts of a tissue to integrate with a polymer. This semester, I explored the wide range of biocompatible polymers that can be assembled inside tissues, and the processes by which this happens. Observing how these polymers interact with organisms may provide new ways to manipulate cell behavior sense electrical and chemical signals inside tissues.