2.1 and 2.4 W cm -2 , respectively. The result was a fluidification of the bilayer of liposomes embedded in the same gel matrix, facilitating the release of the loaded antimicrobial peptide (IK8). In combination with photothermal cell death, the latter contributed to a significant bactericidal activity against both Gram-positive and Gram-negative bacteria. Notably, such hydrogels acted as a sustained drug/Au depot, enabling a single administration to serve for repeated treatments. Similarly, after direct intratumoral injection, hydrogel-embedded Au NPs were effectively immobilized in situ, allowing for repeated irradiation of the tumor site. This approach ensured a consistent increase in temperature effectively slowing down or inhibiting the proliferation of tumor cells. It is worth noting that Au-based nano-objects also possess X-ray attenuation properties, allowing them to be visualized using computed tomography (CT) imaging. By filling the breast cavity with a PNAAm hydrogel containing Au NPs, it was possible not only to implement combined and repeated photo-chemothermal therapy, but also to support reconstructive surgery. In addition to their antimicrobial and antitumor efficacy, AuNPs are finding applications in regenerative medicine. Several examples have reported positive effects on the osteogenic differentiation of mesenchymal stem cells (MSC), making Au-containing materials promising for the treatment and healing of bone defects. Maghemite (Fe2O3) and magnetite (Fe3O4) NPs feature strong magnetic properties, which, combined to their high biocompatibility, make them the most common magnetic nanomaterials for biomedical applications. The main interest of incorporating them into hydrogels stems from their capacity to generate heat when exposed to a magnetic field and serve as contrast agents in magnetic resonance imaging (MRI). Accordingly, these iron-based NPs are highly suitable for controlled drug delivery through magnetic hyperthermia and for non-invasive monitoring. For instance, XG hydrogels containing 10% of Fe3O4 NPs experienced a temperature increases up to 60 °C when exposed to an alternating magnetic field. This rise in temperature enabled encapsulated drugs to be released three times faster than under passive conditions. Moreover, by adjusting the concentration of dispersed NPs it was possible to finetune the T2-MRI contrast enhancement.