Production of methacrylated gelatin: a study on the buffer effect

Methacrylated gelatin (GelMA) is a product of the reaction between methacrylic anhydride (AM) and gelatin and is widely used in tissue engineering. To achieve higher degree of methacrylation (DM) during the reaction pH needs to be controlled. Thus, the use of a pH buffer within the isoelectric point of gelatin is essential for a good reaction yield. The objective of this work is to present a study on the strength of the pH buffer during the reaction of insertion of methacrylic groups in gelatin to find the best concentration to obtain higher DM than described in the literature. Different concentrations of reagents and pH buffer were evaluated, and the reaction product was analyzed by ¹H NMR. The results showed that the carbonate buffer with a concentration of 0.6 M maintained the pH stable in the isoelectric point range and produced GelMA with 95% of DM. (author)