Skin is the largest organ of the human body, protecting it against the external environment. Despite high self-regeneration potential, severe skin defects will not heal spontaneously and need to be covered by skin substitutes. Tremendous progress has been made in the field of skin tissue engineering, in recent years, to develop new skin substitutes. Among them, hydrogels are one of the candidates with most potential to mimic the native skin microenvironment, due to their porous and hydrated molecular structure. They can be applied as a permanent or temporary dressing for different wounds to support the regeneration and healing of the injured epidermis, dermis, or both. Based on the material used for their fabrication, hydrogels can be subdivided into two main groups—natural and synthetic. Moreover, hydrogels can be reinforced by incorporating nanoparticles to obtain “in situ” hybrid hydrogels, showing superior properties and tailored functionality. In addition, different sensors can be embedded in hydrogel wound dressings to provide real-time information about the wound environment. This review focuses on the most recent developments in the field of hydrogel-based skin substitutes for skin replacement. In particular, we discuss the synthesis, fabrication, and biomedical application of novel “smart” hydrogels.

Wound biofilms represent a particularly challenging problem in modern medicine. They are increasingly antibiotic resistant and can prevent the healing of chronic wounds. However, current treatment and diagnostic options are hampered by the complexity of the biofilm environment. In this review, we present new chemical avenues in biofilm sensors and new materials to treat wound biofilms, offering promise for better detection, chemical specificity, and biocompatibility. We briefly discuss existing methods for biofilm detection and focus on novel, sensor‐based approaches that show promise for early, accurate detection of biofilm formation on wound sites and that can be translated to point‐of‐care settings. We then discuss technologies inspired by new materials for efficient biofilm eradication. We focus on ultrasound‐induced microbubbles and nanomaterials that can both penetrate the biofilm and simultaneously carry active antimicrobials and discuss the benefits of those approaches in comparison to conventional methods.

As the largest organ in the human body, the skin has the function of maintaining balance and protecting from external factors such as bacteria, chemicals, and temperature. If the wound does not heal in time after skin damage, it may cause infection or life-threatening complications. In particular, medical treatment of large skin defects caused by burns or trauma remains challenging. Therefore, human bioengineered skin substitutes represent an alternative approach to treat such injuries. Based on the chemical composition and scaffold material, skin substitutes can be classified into acellular or cellular grafts, as well as natural-based or synthetic skin substitutes. Further, they can be categorized as epidermal, dermal, and composite grafts, based on the skin component they contain. This review presents the common commercially available skin substitutes and their clinical use. Moreover, the choice of an appropriate hydrogel type to prepare cell-laden skin substitutes is discussed. Additionally, we present recent advances in the field of bioengineered human skin substitutes using three-dimensional (3D) bioprinting techniques. Finally, we discuss different skin substitute developments to meet different criteria for optimal wound healing.

3D bioprinting bridges tissue engineering and additive manufacturing, however developing bioinks with balanced biological and physical properties remains a challenge. Hyaluronic acid (HA) is a promising base material due to its biocompatibility and cell‐recognition features. An HA‐based bioink is designed using dynamic disulfide‐crosslinking at physiological pH by modifying HA with cysteine moieties. To overcome the slow gelation kinetics typical of disulfide‐crosslinked hydrogels, potassium iodide (KI) is introduced, accelerating gelation in a concentration‐dependent manner. KI not only enhances gelation but also provides radical scavenging properties while maintaining hydrogel integrity. A low KI concentration (50 mm) offers more than a 3 h printing window, ensures cell viability, and facilitates the use of fine needles (32G, 108 µm inner diameter). This enables the fabrication of large (>3 cm) and complex 3D structures. Using this bioink, an osteoarthritis disease model is developed to investigate interactions between human mesenchymal stromal cells (hMSCs) and chondrocytes, demonstrating the immunomodulatory effect of hMSCs on inflammation‐induced chondrocytes. Overall, the HA‐based bioink addresses critical challenges in 3D bioprinting, providing a robust platform for constructing innovative in vitro models and supporting advancements in disease modeling and precision medicine.

Wound biofilms represent a particularly challenging problem in modern medicine. They are increasingly antibiotic resistant and can prevent the healing of chronic wounds. However, current treatment and diagnostic options are hampered by the complexity of the biofilm environment. In this review, we present new chemical avenues in biofilm sensors and new materials to treat wound biofilms, offering promise for better detection, chemical specificity, and biocompatibility. We briefly discuss existing methods for biofilm detection and focus on novel, sensor‐based approaches that show promise for early, accurate detection of biofilm formation on wound sites and that can be translated to point‐of‐care settings. We then discuss technologies inspired by new materials for efficient biofilm eradication. We focus on ultrasound‐induced microbubbles and nanomaterials that can both penetrate the biofilm and simultaneously carry active antimicrobials and discuss the benefits of those approaches in comparison to conventional methods.

In this study, the fabrication of multi‐stimuli‐responsive bowl‐shaped Janus nanomotors integrating platinum nanoparticles coated with cross‐linked Fe ₃ O ₄ @P(BA‐co‐IA) and functionalized with polypyrrole on the surface of iron oxide nanoparticles for potential targeted drug delivery applications is reported. This unique architecture combines three propulsion mechanisms: catalytic motion from asymmetrically deposited platinum in hydrogen peroxide (H ₂ O ₂ ), magnetic guidance from a superparamagnetic iron oxide core, and electric‐field‐driven propulsion via a conductive polypyrrole shell. The nanomotors exhibited precise, directional motion in both biologically relevant neutral (pH 7.4) and acidic (pH 5.8) environments, fueled by 0.5% and 1% (w/w) H ₂ O ₂ . The highest velocity and mean square displacement were observed in neutral medium at 1% H ₂ O ₂ , whereas acidic conditions induced polymer aggregation and reduced mobility. Magnetic fields enabled rapid, oriented transport, and electric fields allowed on‐demand control of speed and direction. The integration of multiple actuation modes into a single nanomotor design offers opportunities for navigation in complex media. This system holds great biocompatibility with human mesenchymal stromal cells, and it offers promise for advanced biomedical applications, targeted transport, and navigation within complex biological environments.