(136g) Controlling Stem Cell Fate within Zwitterionic Hydrogels

We employed zwitterionic hydrogels as platforms to control the self-renewal and differentiation of human mesenchymal stem cells (hMSCs). Firstly, we demonstrate that nonfouling hydrogels composed of pure poly(carboxybetaine) (PCB) allow hMSCs to retain their stem cell phenotype and multipotency, independent of differentiation-promoting media, cytoskeletal manipulation agents, and the stiffness of the hydrogel matrix. In addition, we provided a photodynamic zwitterionic hydrogel capable of reversibly triggering and suspending the differentiation process via manipulating nonspecific interactions between cultured stem cells and the hydrogel. The state of differentiated stem cells can be altered when the hydrogel is exposed to a selected light program, while the differentiation can be immediately suspended when the hydrogel is converted into a pure zwitterionic form by light.