Dynamic Behavior and Spontaneous Differentiation of Mouse Embryoid Bodies on Hydrogel Substrates of Different Surface Charge and Chemical Structures

This study investigated the dynamic behavior and spontaneous differentiation of mouse embryoid bodies (EBs) on hydrogels with varying surface charges and chemical structures, without additional bioactive factors. EBs adhered rapidly to negatively charged poly(sodium p-styrene sulfonate) (PNaSS) hydrogels, promoting spreading, migration, and differentiation into three germ layers, with efficient cardiomyocyte differentiation, similar to gelatin-coated polystyrene plates. On neutral poly(acrylamide) (PAAm) hydrogels, EBs retained their spherical shape and high pluripotency marker expression initially, later showing increased endoderm marker levels. EBs on negatively charged poly(2-acrylamido-2-methyl-propane sulfonic acid sodium salt) (PNaAMPS) gels behaved like those on PAAm gels early on, but later resembled those on PNaSS gels in adhesion and differentiation. The study highlighted the influence of hydrogel surface properties on EBs differentiation.