Hydrolytically stable, functionalizable, and tunable zwitterionic hydrogels for 3D cell culture within a non-fouling microenvironment.

Overview

Zwitterionic hydrogels are promising scaffolds for 3D cell culture due to their strong hydration and resistance to non-specific protein adsorption. Unlike animal-derived matrices like Matrigel, they provide a chemically defined, biologically clean environment for cell growth and differentiation. However, their broader use is hindered by challenges in polymer synthesis and gelation, including poor hydrolytic stability, low yield, slow gelation, and limited stiffness. We report a highly efficient method for synthesizing functional poly(carboxybetaine) (PCB), yielding star-shaped zwitterionic polymers with superior hydrolytic stability, excellent end-group functionalization, and the ability to form hydrogels with tunable stiffness under physiological conditions. The resulting hydrogels incorporate both enzyme-degradable and cell-adhesive peptides, enabling direct encapsulation and release of hPSCs and supporting the culture of various cell types. 3D culture of hPSCs in this system demonstrates robust performance and ease of use, highlighting its potential as a chemically defined, high-performance alternative to Matrigel for 3D cell culture.