Synthesis of PAMAM dendrimer-based fast cross-linking hydrogel for biofabrication

Hydrogels possess great potential in biofabrication because they allow cell encapsulation and proliferation in a highly hydrated three-dimensional environment, and they provide biologically relevant chemical and physical signals. However, development of hydrogel systems that mimic the complexity of natural extracellular matrix remains a challenge. In this study, we report the development of a binary hydrogel system containing a synthetic poly(amido amine) (PAMAM) dendrimer and a natural polymer, i.e., hyaluronic acid (HA), to form a fast cross-linking hydrogel. Live cell staining experiment and cell viability assay of bone marrow stem cells demonstrated that cells were viable and proliferating in the in situ formed PAMAM/HA hydrogel system. Furthermore, introduction of a Arginylglycylaspartic acid (RGD) peptide into the hydrogel system significantly improved the cell viability, proliferation, and attachment. Therefore, this PAMAM/HA hydrogel system could be a promising platform for various applications in biofabrication.