Alginate methacrylate

Alginate is an anionic polysaccharide that is widely used in pharmaceutical and biomedical applications due to its non-animal origin, low toxicity, biocompatibility, and biodegradability. Alginate hydrogels are commonly used to fabricate tissue engineering scaffolds, bioinks for 3D bioprinting, and nanocarriers for drug & gene delivery. While alginate is commonly crosslinked into a hydrogel via ionic-crosslinking with divalent cations (e.g., Ca²⁺), these gels feature limited long-term stability due to exchange reactions and migration of divalent cations from the alginate matrix. To prevent matrix degradation, alginate can be functionalized with reactive groups that can be chemically crosslinked, such as methacrylates. Methacrylate-functionalized alginate can be used to prepare hydrogels by thermal or photochemical crosslinking of the terminal methacrylates. Properties of the resulting hydrogel (e.g., stiffness, swelling ratio, rate of degradation) can be tuned by alginate molecular weight, degree of methacrylate functionalization, and crosslink density.