Search Results (1,101)

Self-healing conductive hydrogels have attracted considerable interest in recent research due to their applications in biomedical and electronic fields. The design and preparation of a functional self-healing conductive hydrogel that features multiple stimuli-responsive properties, adhesion, and tunable mechanical characteristics for a wearable electronic sensor is highly anticipated. In this work, we proposed a hydrogel sensor through free radical polymerization by using host molecule acryloyl-β-cyclodextrin (AC-β-CD), guest molecule of acryloyl-1-adamantanamine (AC-AD), N-isopropylacrylamide (NIPAM), and conductive reduced graphene oxide/β-CD (rGO-CD). The chemical and physical structure, conductivity, de-swelling/swelling behavior, photothermal behavior, mechanical performance, adhesive performance, injectable performance, and self-healing performance of the resultant hydrogels were comprehensively investigated. Human motion detection and cytocompatibility test of hydrogel further demonstrated its potential for wearable electronics applications. Overall, this supramolecular conductive hydrogel might open a new sight to develop a multifunctional flexible sensor. Full article

Smart hydrogel systems with stimuli-responsive properties are increasingly being investigated in combination with advanced additive manufacturing techniques for targeted drug delivery and wound healing in regenerative medicine; however, their clinical translation remains limited by challenges related to material performance, design complexity, and manufacturing scalability. This review analyzes recent developments in smart hydrogel design and 4D-printed scaffolds, with emphasis on programmable and stimuli-responsive architectures. The literature is selectively evaluated based on relevance to (i) hydrogel structure–property relationships, (ii) 3D/4D printing strategies, and (iii) demonstrated performance in drug delivery and wound healing applications. The analysis highlights design approaches enabling spatiotemporal control of drug release and dynamic scaffold behavior, while also examining how fabrication methods influence functional outcomes. Major limitations are critically assessed, including issues of reproducibility, mechanical stability, long-term performance, and the gap between experimental studies and clinical application. Challenges in defining and implementing 4D printing in biomedical contexts are discussed as well. Overall, this review identifies current design trade-offs, outlines priorities for improving reliability and translational potential, and synthesizes emerging trends in 3D and 4D printed hydrogel scaffolds for precision drug delivery and regenerative wound therapy. Full article

This review comprehensively examines magnetic nanomaterials, ferrofluids, and their integration into ferrogel systems, systematically exploring their structural characteristics, dynamic behaviors, preparation techniques, and applications across medical and engineering fields. Structural characterization reveals that particle size and dispersibility directly influence functional efficiency in fluid and gel matrices, such as SAR (specific absorption rate) values in hyperthermia applications. For ferrofluids and magnetic gels, macroscopic behaviors and microscopic mechanisms are governed by key parameters like the magnetic Bond number. Preparation encompasses green synthesis, chemical reagent synthesis, and the cross-linking of these nanoparticles into hydrogel networks. Applications span diverse areas: in medicine, these include targeted hyperthermia, pH-responsive magnetic gel drug delivery, and MRI (magnetic resonance imaging); in engineering, applications range from efficient extraction and triboelectric power generation to magnetically regulated heat transfer and soft gel robotics. The paper also discusses current challenges, including material stability and unclear micro–macro correlations in complex fluid–gel systems, outlining future research directions for multifunctional magnetic materials. Full article

The foaming of hydrogels presents a promising strategy for tailoring mechanical and radiological properties to replicate biological soft tissues for biomedical phantom applications. A computational fluid dynamics (CFD) framework is developed to predict void fraction distribution in alginate hydrogel precursor solutions aerated by air injection through a bottom nozzle. The objective is to use the framework for the design of the foaming system to match the desired gas-fraction distribution and radiological property. Seven parametric cases are investigated, varying inlet air velocity, alginate concentration, and surface tension. Results show that higher inlet velocities promote stronger jet penetration and greater gas accumulation, while increasing alginate concentration confines the bubble plume, with quasi-steady gas fractions displaying a non-monotonic trend with concentration. Elevated surface tension yields broader plume coverage and improved gas distribution uniformity at the expense of peak void fraction. The predicted void fractions map to Hounsfield Unit (HU) values of −34 to −103, corresponding to adipose and fatty breast tissue attenuation (−50 to −150 HU). The peak gas fraction at 5.0 wt% alginate yields −307 HU, approaching published experimental CT measurements for the same formulation (−460 to −233 HU). Full article

Hydrogels derived from biopolymers have attracted considerable interest in biomedical applications because of their biocompatibility and structural similarity to the extracellular matrix (ECM). Bacterial Cellulose (BC), despite being a promising biopolymer for hydrogel preparation, lacks antimicrobial properties itself. To address this drawback, we prepared Probiotic Bacterial Cellulose (PBC) in our laboratory, which has intrinsic antibacterial properties. No research was found on the preparation of a hydrogel using PBC and κ-carrageenan, which motivated us to develop a PBC/κ-carrageenan-based hydrogel. In the study, a novel biocomposite hydrogel system has been developed by integrating PBC with κ-carrageenan, yielding a multifunctional hydrogel with enhanced antibacterial properties and biocompatibility. The novel hydrogel has been evaluated for its structural, physicochemical, antibacterial, and biocompatible properties. Fourier transform infrared spectroscopy (FTIR) analysis confirmed the formation of intermolecular interactions between PBC and κ-carrageenan. Scanning electron microscopy (SEM) images revealed a porous internal morphology and the presence of probiotic bacteria within the hydrogel networks. Porosity analysis and swelling behaviour indicated an elevated water uptake capacity and structural stability. The composite hydrogel demonstrated promising antibacterial properties against pathogenic bacteria Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) and exhibited favourable in vitro biocompatibility. The developed PBC/κ-carrageenan hydrogel exhibits a synergistic combination of porosity, swelling capacity, biocompatibility, and antibacterial activity, making it a potential candidate for healthcare applications viz. wound healing and other tissue engineering applications. Full article

Exopolysaccharides (EPSs) are emerging as sustainable polymers for biomedical hydrogels. Here, we report hydrogels from sulfated EPSs produced by Porphyridium cruentum and ionically crosslinked with Ca²⁺, Ce³⁺, or Cu²⁺ to generate tunable networks with bioactive potential. Rheological analysis showed viscoelastic behavior was primarily governed by cation nature and accessible binding site density, with diminishing gains above 2.5 wt% EPS and limited benefit beyond 10 wt% crosslinker. Ce³⁺ produced the most solid-like gel, Ca²⁺ yielded more thixotropic networks, and Cu²⁺ promoted rapid, heterogeneous crosslinking consistent with fast surface complexation. These network signatures showed distinct in vitro performances. Cation selection tuned antibacterial activity against Staphylococcus aureus and Escherichia coli, with Cu²⁺ achieving rapid bactericidal effects and Ce³⁺ enabling an 8-log reduction after 24 h. The ABTS assay showed that Ca²⁺- and Ce³⁺-crosslinked gels had antioxidant potential (≥40 µM Trolox eq.mg⁻¹); however, antioxidant capacity was assay dependent. Conditioned-medium assays showed ≥75% viability at day 3 for Ca²⁺- and Ce³⁺-crosslinked gels against human dermal fibroblasts (HDFs), while only Ce³⁺-crosslinked gels were cytocompatible against human keratinocytes (HaCaTs). Cu²⁺-crosslinked gels were highly cytotoxic across all tested conditions. Macrophage cytokine readouts (TNF-α and IL-6) indicated formulation-dependent immunobiological response. This work establishes microalgal EPSs as versatile polymers and links crosslinking chemistry to rheological modulation and multifunctional biomedical performance, while direct wound-healing efficacy remains to be demonstrated in future in vivo or wound repair functional models. Full article

Fibrin gel, a protein-based polymer naturally generated during coagulation, has garnered attention in the biomedical field for applications such as fibrin glue, due to its specific physical and biological properties. Despite it, low mechanical strength and rapid degradation limited its utilization for biomedical applications. This study presents a reproducible protocol for the synthesis of pure fibrin hydrogels, aimed at achieving predictable structural properties through the precise calibration of fibrinogen and thrombin concentrations. By examining the mechanical and morphological characteristics, as well as the relationship between reagent concentrations and structural integrity, this research assesses impacts on swelling behavior, water absorption, and overall stability. Through a comprehensive analytical approach, we identified an optimal formulation, specifically 2.25 mg/mL fibrinogen and 1.375 U/mL thrombin, that effectively balances structural integrity with high cytocompatibility. The results demonstrate that this calibrated approach ensures high procedural reproducibility and a well-defined hydrogel architecture without the need for exogenous chemical cross-linkers. This work provides a robust methodological framework to overcome the common lack of reproducibility in fibrin-based hydrogel studies, positioning these materials as highly reliable candidates for advanced 3D in vitro models and biomedical applications. Full article

As the most abundant natural polymer on Earth, cellulose offers distinct advantages including renewability, biocompatibility, and modifiability. Among its various morphologies, spherical cellulose hydrogels (SCHs) represent a particularly versatile form ranging from micrometer to millimeter scales. They possess a unique hydrophilic 3D network, excellent flowability, high specific surface area, and outstanding mechanical stability, demonstrating great potential for biomedical applications. This mini-review highlights the primary bottom-up fabrication strategies for SCHs, including dripping, spraying, emulsion, and microfluidics, and the mechanisms by which different fabrication processes regulate their size, morphology, and structure are elucidated. On this basis, the recent advancements in SCHs across key biomedical domains, specifically in chromatographic separation, controlled drug delivery, tissue engineering, and wound healing, are discussed. Finally, the current challenges and future directions in this field are summarized and predicted, aiming to provide a reference for the development and application of high-performance cellulose-based biomaterials. Full article

Four-dimensional (4D) printing integrates additive manufacturing with stimuli-responsive materials to fabricate biomedical implants and functional healthcare devices that undergo programmed, time-dependent changes in shape or function. Unlike static 3D-printed constructs, 4D-printed systems can respond to clinically relevant stimuli such as temperature, hydration, pH, light (including near-infrared), magnetic fields, or electrical inputs. These triggers drive defined actuation mechanisms, most commonly thermomechanical shape-memory recovery, swelling-induced morphing, and magnetothermal activation. This review synthesizes the principal material platforms used for biomedical 4D printing, including shape-memory polymers and alloys, hydrogels, liquid-crystal elastomers, and responsive composites, and links material choice to device behavior and translational feasibility. Applications are discussed across self-expanding stents, cardiac occluders, tissue-engineered constructs, implantable drug delivery systems, and adaptive wearables. Key translational challenges include sterilization compatibility, manufacturing reproducibility and quality control, safe stimulus delivery, predictable biodegradation and long-term biocompatibility, and regulatory pathway definition. Full article

Carbon quantum dots (CQDs) and stimuli-responsive hydrogels are advanced functional materials whose hybridization yields CQD-enhanced stimuli-sensitive hydrogels, opening new interdisciplinary avenues for smart material applications. This review systematically summarizes the latest advances in these composites, focusing on synthetic strategies, structure–property modulation mechanisms, and practical applications. Distinct from existing reviews that either investigate CQDs or hydrogels independently or discuss their composites in a single research field, this work features core novelties in integration strategy, application scope and critical analysis: it systematically compares the advantages, limitations and applicable scenarios of three typical CQD–hydrogel integration approaches (physical entrapment, in situ synthesis, covalent conjugation), comprehensively covers the multi-field application progress of the composites and conducts in-depth cross-field analysis of their common scientific issues and technical bottlenecks. By incorporating CQDs, the composites achieve remarkable performance optimizations: 40% improved mechanical toughness, sub-ppm-level heavy metal-sensing sensitivity, and over 80% organic dye photocatalytic degradation efficiency, addressing pure hydrogels’ inherent limitations of insufficient strength and single functionality. These enhancements enable sophisticated applications in biomedical field (real-time biosensing, controlled drug delivery), environmental remediation (pollutant detection/degradation), energy storage, and flexible electronics. The synergistic interplay between CQDs and hydrogels facilitates precise single/multi-stimulus responsiveness (pH, temperature, light), a pivotal advance for precision medicine and intelligent environmental monitoring. Despite promising progress, the large-scale practical application of CQD–hydrogel composites still faces prominent challenges: the difficulty in scalable fabrication with the uniform dispersion of CQDs in hydrogel matrices, poor long-term stability of most composites under physiological cyclic stress (service life < 6 months in practical tests), and low accuracy in discriminating multi-stimuli in complex real-world matrices. Future research should prioritize biomass-based eco-friendly CQD synthesis, machine learning-aided multimodal responsive systems, and 3D bioprinting for scalable manufacturing. Full article

In this study, a hydrogel was developed based on a chondroitin sulfate–iron complex (CSFe) incorporated into a sodium alginate matrix. The CSFe complex was first prepared through the interaction of chondroitin sulfate (CS) with Fe³⁺ ions, achieving an iron content of 2.06%. Structural characterization confirmed that Fe³⁺ coordinated with the carboxyl, sulfate, and N-acetyl groups of CS, resulting in increased molecular weight and altered physicochemical properties. The CSFe complex exhibited significant antibacterial activity against Escherichia coli and Staphylococcus aureus (S. aureus), and was further incorporated into a sodium alginate matrix to form an injectable hydrogel with favorable physicochemical properties such as spreadability, shear-thinning behavior, and a compact porous microstructure. In a mouse model of S. aureus-infected wounds, the CSFe hydrogel significantly accelerated wound closure, reduced the levels of pro-inflammatory cytokines (TNF-α and IL-6), and increased the anti-inflammatory cytokine IL-10, indicating potent anti-infective and immunomodulatory functions. Overall, this work presents a multifunctional CSFe-incorporated hydrogel system that integrates antibacterial, anti-inflammatory, and tissue-regenerative properties, offering a promising strategy for infected wound healing and highlighting the potential of trivalent iron–polysaccharide coordination complexes in the development of advanced biomedical materials. Full article

Hybrid supramolecular–nanocomposite hydrogels based on polyethylene glycol (PEG), β-cyclodextrin–adamantane host–guest interactions, and silica nanoparticles represent an important class of hierarchical soft materials with tunable viscoelastic and transport properties. This review critically analyzes recent progress in cyclodextrin–silica hybrid PEG hydrogels, focusing on the mechanistic coupling between stiffness, stress relaxation, and molecular transport arising from the interplay between reversible supramolecular crosslinks and nanoparticle-induced confinement effects. Particular attention is given to how host–guest exchange kinetics regulate dynamic bond rearrangement and affinity-mediated retention of hydrophobic cargo, while silica nanoparticles enhance mechanical reinforcement and modify diffusion pathways through tortuosity and interfacial polymer–particle interactions. The analysis highlights how nanoparticle size, loading level, and surface functionalization influence relaxation spectra and network topology, as well as how environmental stimuli may affect supramolecular bond stability and overall material performance. Comparison with alternative inorganic fillers and mesoporous silica architectures further clarifies the specific advantages of silica in achieving balanced mechanical stability and controlled transport behavior. Overall, current evidence indicates that hybrid CD–silica networks enable partial decoupling of stiffness, relaxation dynamics, and diffusion, although complete independence remains constrained by fundamental polymer physics relationships. These insights support the development of predictive structure–property frameworks for advanced biomedical and controlled release applications. Full article

Chitin-based hydrogels have emerged as a versatile and sustainable material with significant potential in biomedical, environmental, and energy applications. Derived from the abundant biopolymer chitin, these hydrogels exhibit exceptional biocompatibility, biodegradability, and tunable physicochemical properties. This review highlights advances in chitin-based hydrogels, focusing on solvent systems, crosslinking strategies, and structural modifications to enhance mechanical strength, swelling, and stimuli responsiveness. Key applications include wound healing, drug delivery, tissue engineering, and environmental remediation, where their high-water retention, enzymatic degradability, and eco-friendly nature are particularly advantageous. Furthermore, innovations such as nanoparticle incorporation and chemical derivatization (e.g., carboxymethylation, hydroxypropylation) have expanded their utility in energy devices and smart sensors. Despite these advances, challenges remain in optimizing the energy efficiency of production methods for industrial scalability. This review provides a comprehensive overview of the current state of chitin-based hydrogels, offering insights into future directions for research and development in this promising field. Full article

Utilizing food-derived bioactive polysaccharides in advanced biomedical applications offers significant potential. To effectively harness the inherent bioactivity of Poria cocos, a renowned edible and medicinal fungus, we developed a multifunctional double-network composite hydrogel (CPS) via a feasible one-pot strategy. This was achieved by incorporating functional carboxymethyl pachymaran (CMP) into a matrix of food-grade sodium alginate (SA) and polyacrylamide (PAM). This formulation endows the hydrogel with excellent extensibility, rapid self-healing capabilities, and strong tissue adhesion, all while preserving the biological activity of the natural macromolecules. In a mouse full-thickness skin defect model, the CPS significantly accelerated wound recovery, achieving a healing rate of 51.17 ± 4.87% by day 7. Mechanistically, the food-derived CMP synergistically promoted skin tissue regeneration by downregulating the expression of the early pro-inflammatory cytokine TNF-α and upregulating the angiogenic marker CD31, thereby actively modulating the local microenvironment. Ultimately, these findings demonstrate the viability of using edible fungal polysaccharides as primary bioactive components in advanced wound dressings, providing a novel approach for utilizing food macromolecules in biomedicine. Full article

Over the past decade, antibacterial materials have become a promising strategy to address both antibiotic-resistant and biomaterial-associated infections in clinical settings. Despite substantial progress, a gap remains between promising antibacterial performance in vitro and limited therapeutic outcomes in vivo. Herein, we present a mechanistic framework for understanding formulation-dependent antibacterial performance across five representative formulation architectures: nanoparticle-based systems, nanofibrous scaffolds, hydrogel matrices, surface coatings, and vesicular or microencapsulated carriers. We impart how structural organization and delivery dynamics regulate antibacterial mechanisms such as contact-mediated killing, controlled therapeutic release, and reactive oxygen species (ROS) generation and discuss their context-dependent suitability for diverse infection scenarios; these include acute wound infections, biofilm-associated implant infections, and chronic infected wounds. Particular emphasis is placed on factors contributing to the frequent failure of high in vitro log reduction efficacy translating into clinical success, including protein corona formation, biological barrier penetration, and dynamic host–pathogen interactions. Finally, we propose a comparative formulation-selection framework based on infection type, tissue environment, and therapeutic objectives to guide the rational design of next-generation antibacterial materials. This perspective bridges the gap between material innovation and clinical translation by highlighting formulation architecture as a central determinant of antibacterial performance in biomedical applications. Full article