Frontal Polymerization-Enabled Rapid Fabrication of Gelatin-Containing Hydrogels with Good Mechanical and Biological Properties

A time-saving approach to gelatin-based hydrogels with versatile properties is highly desirable. Herein, we report the rapid fabrication of new gelatin-containing hydrogels with favorable mechanical properties, biocompatibility and antibacterial capability. Frontal polymerization (FP) of acrylic acid (AA), acrylamide (AM), hydroxypropyl acrylate (HPA) with gelatin methacryloyl (GelMA) enables the rapid formation of multifunctional hydrogels within 7 min, providing a highly efficient route for gelatin-based hydrogel fabrication. The effect of GelMA content on FP features and hydrogel properties was systematically investigated. The resultant hydrogels show attractive collective properties with tensile strength up to 101.3 kPa, elongation at break up to 227.7%, cell viability of 96% after 24 h, and antibacterial activity against S. aureus (92.2%). In addition, the FP of the hydrogels with use of forsythia-derived carbon dots (F-CDs) as bioactive nanofillers is explored, conferring the hydrogels with enhanced mechanical performance and biocompatibility, demonstrating the applicability of this FP strategy upon incorporating functional additives. This work provides a simple and effective approach for the rapid preparation of gelatin-containing hydrogels with versatile functions promising for biomedical applications such as wound healing and tissue engineering.