3D-printed GelMA-Fe-GQD magneto-hydrogel as a smart platform for triple-negative breast cancer hyperthermia

Designing multifunctional hydrogels that combine structural tunability with therapeutic responsiveness remains a key challenge in translational cancer nanomedicine. Here, we report the development of a GelMA-Fe-GQDs nanocomposite hydrogel engineered for 3D bioprintability and magnetically triggered hyperthermia. Physicochemical characterization confirmed controlled swelling (310 ± 28%) and enzymatic stability, with rheological testing revealing reinforced viscoelasticity and partial recovery (∼17.2 ± 6%) after high-strain disruption. The hydrogel exhibited ideal printability, producing stable filaments and droplets with consistent deposition fidelity. Under an alternating magnetic field (AMF) 313 kHz, ∼18 kA·m^-1, GelMA-Fe-GQDs hydrogels exhibited concentration-dependent heating, surpassing the therapeutic hyperthermia threshold (>42 °C) within 10 min at 1-2 mg·mL^-1, with a calculated specific absorption rate (SAR) of ∼175 W·g^-1 of Fe₃O₄. Thermal imaging confirmed uniform and localized heating within composite-containing regions. In vitro assays with triple negative breast cancer cells (TNBC) revealed high initial viability in both 2D and 3D cultures, with effective thermal ablation observed upon AMF exposure, validating the cytotoxic efficacy of magnetically induced heating. Collectively, these results establish GelMA-Fe-GQDs hydrogel as a printable, mechanically tunable, and magneto-responsive platform with potential for integration into 3D tumor models and localized cancer hyperthermia therapy.