ABSTRACT Wound infections impede healing and account for nearly half of chronic wound cases (∼6.7 million people), posing significant clinical and economic burdens on healthcare. Antibiotics treat infections, but their misuse has accelerated antimicrobial resistance. A holistic approach to wound infection management includes exudate handling, potent antibacterial activity, mitigating multidrug resistance, regulating therapeutic release, and promoting healing. However, existing therapeutic options remain insufficient to address wound healing's multifactorial nature. This study presents silver ion (Ag + ) exchange‐based hybrid dressing formulated from an aliphatic diisocyanate‐based prepolymer instead of conventional diisocyanates, biocompatible foaming agents, and a crosslinker‐free hyaluronic acid coating. According to BS EN 13726 and ASTM D3574‐17 standards, the dressing showed excellent exudate handling capacity, burst and sustained release of Ag + , and comfort wear characteristics. Despite low Ag + concentrations (40–60 wt.%), the dressing demonstrated excellent antimicrobial efficacy (>99%) against Staphylococcus aureus and its drug‐resistant strain in in vitro and in vivo studies, comparable to a leading commercial dressing (Biatain). In a full‐thickness S. aureus‐ infected Wistar rat model, the dressing facilitated complete wound closure by day 18 and enhanced tissue regeneration, as evidenced by hematoxylin and eosin staining, Masson's trichrome, and immunohistochemical evaluations. Overall, dressings regulate infection and expedite healing, underscoring their significance in clinical wound care.
ABSTRACT Oligo[poly(ethylene glycol) fumarate] (OPF) is an efficient gel‐forming macromer for challenging tissue engineering applications, including repair of the spinal cord (SC) after complete lesion. Existing OPF‐derived SC‐bridging hydrogels are being applied with cellular products and/or electrical stimulation to promote regeneration. A novel biologics‐free composite OPF hydrogel was designed as a ready‐to‐use neuroactive scaffold with defined (bio‐)chemical, porous structure, and multi‐channel system to support cellular/axonal growth. It was constructed as a highly permeable macroporous cryogel and activated with compositions of IKVAV, RGD, GHK, and LRE cytoadhesive/signaling peptide derivatives via cyclodextrin–adamantane affinity binding to create a synthetic ECM analog. The four‐peptide composition promoted neural cell growth and morphological differentiation in vitro. Relationships between OPF macromer concentration, channel diameter, and biomechanical properties were established, enabling development of OPF scaffold with balanced architecture. Its longitudinal compressive strength was adjusted to SC‐bridging conditions by comparison with SC explants. A mini‐pig SC transection and bridging model was optimized to perform a pilot in vivo study that showed scaffold biointegration, structural maintenance, and host cell infiltration following acute implantation. These findings demonstrate the potential of OPF cryogel scaffold for SC repair and provide a strong foundation for studying its long‐term effects upon complete SC lesion.
ABSTRACT Brachytherapy (BT) delivers high‐dose localized irradiation through the direct implantation of radionuclides into tumor sites and remains an important treatment modality for solid tumors. However, conventional BT is limited by damage to surrounding normal tissues, potential leakage of radionuclides, and the restricted efficacy of single‐modality treatment. Hydrogels, owing to their injectability, biocompatibility, and tunable functionality, offer promising solutions to these challenges. This review summarizes recent advances in two principal applications of hydrogel‐assisted BT. On the one hand, hydrogels can serve as biodegradable spacers that increase the distance between the target region and organs at risk, thereby reducing radiation exposure to normal tissues such as the rectum and urethra; this approach has demonstrated significant dosimetric advantages and reduced toxicity in prostate and gynecological cancers. On the other hand, hydrogels can function as localized delivery platforms for radionuclides, enabling precise radiotherapy, while also supporting the co‐delivery of chemotherapeutic agents, nanoparticles, and immunomodulators to construct dual‐ or multimodal synergistic treatment strategies. Their potential for enhanced therapeutic efficacy has been demonstrated across various tumor models. Finally, this review critically examines the key technological and clinical translational challenges currently limiting hydrogel‐assisted BT and outlines future research directions for more effective and precisely targeted therapies.
ABSTRACT Recent advances in enzymatic polyester depolymerization have highlighted the potential of biocatalysis for sustainable plastic recycling. In contrast, efficient enzymatic strategies for polyamide (PA) degradation remain limited. Here, we investigate how complementary amidases influence product formation during the enzymatic treatment of bulk nylon‐6 (PA6) and nylon‐6,6 (PA66). Guided by previously established substrate preferences, enzyme combinations are designed to couple NylC‐mediated oligomer cleavage with downstream conversion by NylB or cyclic oligomer ring‐opening by NylA. Sequential enzyme treatments demonstrate efficient conversion of characteristic PA6‐ and PA66‐derived intermediates, while one‐pot systems enable coordinated downstream conversion at 34°C–40°C. For PA6, NylB efficiently converts the NylC‐generated 6‐aminohexanoic acid dimer to 6‐aminohexanoic acid, whereas for PA66, NylA selectively redirects accessible cyclic PA66‐derived species toward the corresponding linear repeat‐unit product. These changes in product distribution are not accompanied by a substantial increase in the overall amount of soluble polymer‐derived material. The detected soluble products represent less than 1% of the initial polymer mass under the investigated conditions, demonstrating that overall soluble product release remains limited. Together, these results show that complementary amidases can control downstream intermediate conversion and product selectivity during enzymatic nylon depolymerization.
In recent studies, oxygen (O2) delivery biomaterials have been developed to reduce hypoxia-induced problems in, e.g., tumor tissues. However, none of these studies have used inhibitory effects of probiotics in combination therapies with O2 and anticancer drugs for advanced cancer treatment applications. In this study, we report a new probiotic-enriched 3D-printed biomaterial (3D-BioHybrid-DOX/SPEP) that is capable of O2, probiotic, and acidic pH (pH 6.0) sensitive anticancer drug (Doxorubicin = DOX) co-release. 3D-BioHybrid-DOX/SPEP shows sustained O2 and pH-responsive anticancer drug release over 14 days. The release of short-chain fatty acids, including butyric acid, was detected on days 1 and 7 of incubation, indicating that the O2 delivery component of the system supports probiotic viability while mitigating the toxic effects of DOX. The CFU results show that the 3D-BioHybrid-DOX/SPEP supports probiotic viability at 1 and 7 days of incubation. In vitro cell experiments indicate that the healthy cell viability is ca. 2 times higher than cancer cells after 1 and 7 days of incubation at hypoxia conditions in 3D-BioHybrid-DOX/SPEP due to the co-administration of O2, DOX, and probiotics.
