Polymer Surface Interacts with Calcium in Aqueous Media to Induce Stem Cell Assembly

Bioinspired surface with functional group rearrangement abilities are highly desirable for designing functional materials. Calcium ion (Ca2+) is a pivotal life element and the ion transport is tightly regulated through calcium channels. It is demonstrated here that Ca2+ can be transported by polymer surface to induce cell assembly. A series of polyurethane materials is synthesized with different abilities to rearrange the surface functional groups in response to aqueous environment. It is observed that surface recruitment of carboxyl and amino groups from the bulk material can interact with Ca2+ and facilitate its translocation from aqueous media into cells. The surface rearrangement of functional group triggers the calcium trafficking and turns on signals involving cell merging and assembly. This observation provides an insight on adjusting material-calcium interaction to design nature-inspired smart interfaces to induce cell organization and tissue regeneration.