Crosslinking starch with Diels-Alder reaction: water-soluble materials and water-mediated processes

The click Diels-Alder cycloaddition is a one-step high-yield reaction that does not require catalysts, does not generate side products and can be performed at mild conditions in an aqueous medium, representing a good method for biomaterials coupling and synthesis. It exploits functional groups that can be grafted onto natural polymers or other molecules and can be used for the preparation of biomaterials such as biocompatible hydrogels, a nascent field of application of the Diels-Alder reaction. If performed in an aqueous medium, at biological pH and body temperature, it can be used in internal body systems for drug and cell release. Here we report the grafting of the furan ring from furfuryl alcohol to chemically oxidized starch and its crosslinking via the Diels-Alder reaction, in aqueous medium, at 37 degrees C, mimicking the body conditions in vitro. Since the functional groups used in this chemical strategy are sparingly studied for such applications, and their behavior is not described in the literature, the biocompatibility of the crosslinked starch as well as that of the precursor reagents were evaluated by cytotoxicity tests using GM07492 human cells. The results reveal that the furan-crosslinked starch is a promising candidate for cell encapsulation and delivery within the body. (c) 2022 Society of Industrial Chemistry.

Automated summary

The click Diels-Alder cycloaddition is a highly efficient reaction for biomaterials coupling and synthesis, which can be performed without catalysts, generate no side products, and take place under mild conditions in an aqueous medium. The grafting of furan ring to chemically oxidized starch and its crosslinking via the Diels-Alder reaction, mimicking body conditions, shows promise for cell encapsulation and delivery. The biocompatibility of the crosslinked starch was assessed through cytotoxicity tests, indicating its potential applications in the field.