Thermally responsive injectable hydrogel incorporating methacrylate-polylactide for hydrolytic lability

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Tissue Engineering

Background:

• Injectable thermoresponsive hydrogels are valuable for tissue support and drug/cell delivery.
• Existing hydrogels require improved mechanical properties and adjustable degradation rates.

Purpose of the Study:

• To synthesize and characterize novel bioabsorbable, thermally responsive hydrogels.
• To enhance mechanical strength and control degradation profiles for biomedical applications.

Main Methods:

• Copolymerization of N-isopropylacrylamide (NIPAAm), 2-hydroxyethyl methacrylate (HEMA), and methacrylate-polylactide (MAPLA).
• Characterization using NMR, FTIR, GPC, and assessment of thermal transitions and mechanical properties.
• Evaluation of degradation in PBS and in vitro cytotoxicity testing.

Main Results:

• Synthesized poly(NIPAAm-co-HEMA-co-MAPLA) hydrogels exhibited tunable lower critical solution temperatures (12.4-16.2°C).
• Hydrogels demonstrated strong mechanical properties (up to 100 kPa tensile strength) and reached ~45% water content post-gelation.
• Complete degradation occurred within 6-7 months in PBS, with faster degradation linked to higher MAPLA content. No cytotoxicity was observed.

Conclusions:

• Novel MAPLA-containing hydrogels offer enhanced mechanical strength and controllable degradation.
• These materials are suitable for injection therapies requiring mechanical support and tunable resorption.
• The developed hydrogels present promising new options for advanced biomaterial applications.