Synthesis of Thermal Polymerizable Alginate‐GMA Hydrogel for Cell Encapsulation

Alginate is a negative ionic polysaccharide that is found abundantly in nature. Calcium is usually used as a cross‐linker for alginate. However, calcium cross‐linked alginate is used only for in vitro culture. In the present work, alginate was modified with glycidyl methacrylate (GMA) to produce a thermal polymerizable alginate‐GMA (AA‐GMA) macromonomer. The molecular structure and methacrylation (%DM) of the macromonomer were determined by 1H NMR. After mixing with the correct amount of initiator, the AA‐GMA aqueous solution can be polymerized at physiological temperature. The AA‐GMA hydrogels exhibited a three‐dimensional porous structure with an average pore size ranging from 50 to 200 μm, directly depending on the macromonomer concentration. Biocompatibility of the AA‐GMA hydrogel was determined by in vivo muscle injection and cell encapsulation. Muscle injection in vivo showed that the AA‐GMA solution mixed with initiator could form a hydrogel in situ and had a mild inflammatory effect. Human umbilical vein endothelial cells (HUVECs) were encapsulated in the AA‐GMA hydrogels in situ at 37°C. Cell viability and proliferation were unaffected by macromonomer concentrations, which suggests that AA‐GMA has a potential application in the field of tissue engineering, especially for myocardial repair.