Injectable Hydrogel Based on Oxidized Agarose–Carboxymethyl Chitosan with Potential Use in Biomedical Applications

A hydrogel based on carboxymethyl chitosan (CMCh) and oxidized agarose (OA) was prepared and characterized by evaluating properties such as gelation, injectability, syringeability, mechanical properties, self-healing capacity, and swelling ratio. The hydrogel has a stable gel consistency at 37 °C. However, it could be injected through a 21 G-gauge needle with a maximum force of 18.37 ± 1.4 N. Also, applying a load of 18.24 N for 15 s gave a syringeability percentage of 54.08 ± 3.73%, indicating good injection performance. The hydrogel exhibited a compressive strength of 46.28 ± 7.44 kPa and a Young's modulus of 8.67 ± 0.73 kPa, indicating the formation of a flexible crosslinked network. Additionally, it was observed that storage at 4 °C can alter the previously mentioned properties. Finally, it was found that the hydrogel can self-repair after 48 h and swell up to 2 530 ± 388% in 15 days. Considering this, the obtained hydrogel has the potential to be implemented in biomedical applications.