Search Results (1,076)

Nanotheranostic platforms integrating diagnostic and therapeutic functions within a single system have attracted significant attention in precision medicine. However, conventional nanotheranostics based on systemic administration often suffer from off-target accumulation, limited retention at disease sites, and dose-limiting toxicity. To address these limitations, hydrogel-integrated nanotheranostic systems have emerged as a promising strategy for achieving localized diagnosis and therapy with improved spatial control and safety. This review provides a comprehensive overview of recent advances in hydrogel–nanomaterial nanotheranostic platforms, focusing on their design principles, diagnostic capabilities, and therapeutic applications. We discuss the complementary roles of hydrogels and nanomaterials, where hydrogels function as localized reservoirs and tissue interfaces, and nanomaterials provide imaging and therapeutic functionalities. Key integration strategies including physical encapsulation, chemical conjugation, and in situ nanoparticle formation are systematically compared. We further summarize localized diagnostic modalities such as real-time imaging and therapy monitoring, and highlight research-driven applications in cancer treatment, inflammation and infection management, and tissue regeneration. Finally, major translational challenges and future perspectives toward personalized, image-guided local theranostics are discussed. Overall, hydrogel-based nanotheranostic platforms represent a versatile approach for next-generation localized precision medicine. 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

Kappa-carrageenan (κ-CRG) forms thermo-reversible physical hydrogels via a coil–helix transition and helix bundling, but its sulfate-driven electrostatic repulsion limits mechanical robustness and control over aqueous disintegration. Here, we show that plant-derived polyphenols reprogram κ-CRG gel through sulfate-directed binding in a structure-dependent manner. Tannic acid (TA) selectively engages κ-CRG sulfate groups, yielding transparent gels and a >5-fold increase in storage modulus, whereas the same TA triggers turbidity and precipitation in sulfate-free agarose, supporting sulfate-mediated specificity. Using monomeric pyrogallol as a galloyl analogue, we demonstrate that monovalent interactions partially reinforce κ-CRG but lack cooperative stabilization. Intervention timing further separates mechanism. Pyrogallol produces pathway-dependent mechanics and gelation temperature, while TA is stage-insensitive, consistent with multivalent network annealing. In simulated gastric/intestinal fluids, pyrogallol/κ-CRG gels retain morphology longer, whereas TA/κ-CRG ones disintegrate rapidly yet exhibit strong adhesion to rough substrates and human skin. These findings provide a fully food-grade route to tune κ-CRG mechanics, thermal behavior, adhesion and programmed disintegration. Full article

Fieldwork carries a high risk of irregular, non-compressible traumatic wounds, which often initiate a vicious cycle of “traumatic bleeding-insect bite-secondary infection”. Conventional dressings cannot combine rapid hemostasis with physical protection against venomous insects, creating an urgent demand for multifunctional field trauma dressings. To solve this problem, this study developed a shape-adaptive bilayer hydrogel that concurrently provides rapid hemostasis, promotes wound repair, and acts as a robust physical barrier. The hydrogel adopts a layered design: the bottom layer (PPTY) achieves autogelation within 3 s upon blood contact, while the top armor protective layer (AP) withstands pressures up to 942 kPa. By incorporating chitosan and sodium citrate into the AP precursor solution, the hydrogel achieved in situ formation within 50 s and developed a stable self-renewing armor layer. The tightly bonded bilayer showed complementary functions. In rat models of femoral artery puncture and tail vein bleeding, PPTY-AP hydrogel significantly reduced blood loss and shortened hemostasis time. Moreover, the hydrogel demonstrated excellent tissue adhesion and moisture retention capacity, promoting full-thickness skin wound healing. This multifunctional, rapidly deployable hydrogel presents a promising solution for field trauma management and offers a new design paradigm for advanced wound dressings. Full article

Flexible electrolyte-gated synaptic field-effect transistors (EGFETs) have emerged as a promising platform for neuromorphic visual systems, owing to their low-voltage operation, diverse synaptic plasticity, and exceptional mechanical flexibility. In particular, gel-based electrolytes, including hydrogels and ion gels, play a pivotal role as functional gate dielectrics, enabling efficient ion transport and strong ion–electron coupling through electric double-layer (EDL) formation. By leveraging these unique properties at the semiconductor/gel interface, EGFETs can effectively emulate essential biological synaptic behaviors, including short-term and long-term plasticity under optical stimulation. The inherent compatibility of EGFETs with a broad range of semiconductor channels, gel electrolytes, and flexible substrates enables the development of wearable and conformable neuromorphic platforms that seamlessly integrate sensing, memory, and signal processing within a single device architecture. Recent advances in gel material engineering, such as polymer network design, ionic modulation, and nanofiller incorporation, have significantly improved ion transport dynamics, interfacial stability, and device performance. Despite remaining challenges related to ion migration stability, multi-physical field coupling, and large-area device uniformity, these developments have substantially advanced the practical potential of gel-based systems. This review provides a comprehensive overview of the operating mechanisms, gel-based material systems, synaptic functionalities, mechanical reliability, and future prospects of flexible electrolyte-gated visual synapses, highlighting their considerable potential for next-generation intelligent perception and artificial vision technologies. Full article

Chronic wounds resulting from bacterial infection remain one of the main challenges in clinical practice. There is a pressing need to develop an injectable hydrogel sealant with multifunctional properties, including remodeling capabilities, self-healing, painless removal, and antibacterial activity, to promote tissue remodeling. In this work, aldehyde carboxymethylated agarose (ACMA) is employed for the first time as a bio-template. Dopamine (DA) is introduced onto the ACMA template via a reversible Schiff-base reaction, endowing it with biomineralization properties to synthesize DA-modified ACMA-Ag nanoparticles (ACMA-DA-Ag). Further, the prepared ACMA-DA-Ag, which possesses both antibacterial activity and injectable behavior, is incorporated into a guar gum hydrogel through the formation of borate/diol bonds, thereby forming a multiple-dynamic-bond crosslinked network. This hydrogel demonstrates adequate mechanical strength, injectability, remodeling capabilities, and self-healing performance. It can reassemble into a new hydrogel within 4 ± 0.6 min upon simple physical contact, and supports tissue adhesion. Furthermore, the hydrogel effectively covers irregular-shaped wound and can be removed without causing secondary injury. More importantly, this multifunctional hydrogel is cost-effective, easy to synthesize, and simple to use, significantly accelerating skin regeneration and promoting the formation of skin appendages, such as hair follicles. The outcome of this research not only serves a tissue sealant for wound healing, but also presents a new strategy for creating novel polysaccharide-based biomaterials. Full article

Background/Objectives: Skin cancers belong to the most frequent cancer type with over a million cases per year. Presently, transdermal drug delivery systems (TDDS) are an attractive drug delivery route, but they still face some limitations due to the resistance of human skin. Methods: Here, Sonidegib, PEDOT:PSS, and gelatins were employed as the model drug, drug carrier, and drug matrix, respectively. Results: Gelatin hydrogels were fabricated via the physical crosslinking to avoid toxicity towards the human skin. PEDOT:PSS was synthesized by chemical oxidative polymerization as the drug carrier. Sonidegib first interacted with PEDOT:PSS before they were embedded into the gelatin hydrogels. In the release and release-permeation experiments, the amounts of Sonidegib released and permeated were investigated under the effects of gelatin types, concentrations, pH values, PEDOT:PSS, and electrical voltages. For the effect of gelatin types, the BG gelatin provided higher amounts of Sonidegib release than PG from the higher electrorepulsive force. Under applied electrical voltages and with PEDOT:PSS present, the amounts of Sonidegib release and release-permeation amounts increased as PEDOT:PSS assisted in providing higher electroosmosis and electrorepulsive forces. Conclusions: In summary, PEDOT:PSS in the BG hydrogel is demonstrated here as a potential drug carrier to improve the Sonidegib release and release-permeation iontophoretically for TDDS. 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

Background: Crosslinker-free, pH-induced hydrogels offer a green alternative for food preservation but often lack mechanical robustness. Objective: In this study, we developed a ternary hydrogel from cod myofibrillar protein (CP), sodium alginate (SA), and Ulva prolifera-derived insoluble dietary fiber (IDF) to enhance structural and preservation properties. Methods: Hydrogels with 0–3% IDF were characterized to assess their texture, water-holding capacity (WHC), and microstructure. Based on the balance between reinforcement and macroscopic processability, the 2% IDF formulation was selected for the shrimp preservation trial, which was conducted over 15 days at 4 °C. Results: Incorporation of 2% IDF significantly increased gel hardness (from 278.0 ± 6.8 g to 393.0 ± 1.8 g; p < 0.01, n² = 0.87) and WHC (from 60% to 84.3 ± 2.1%; p < 0.01). In preservation tests, the CP-SA-IDF coating maintained TVB-N at 41.62 ± 3.7 mg/100 g, significantly lower than the control (78.65 ± 4.5 mg/100 g; p < 0.01) and inhibited microbial growth (TVC: 6.9 ± 0.3 log CFU/g vs. control 9.1 ± 0.4 log CFU/g; p < 0.05). A combined freshness index demonstrated superior overall preservation efficacy (0.82 vs. 0.49 in control; p < 0.05). Conclusions: IDF reinforces the CP-SA network via hydrogen bonding and physical entanglement, creating an effective edible coating for aquatic product preservation. 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

In the current study, bioactive-loaded hydrogels were developed with k-carrageenan (1%), and water was replaced with infusions of Urtica dioica L., which modulated the polymer chains to create more robust networks. Urtica dioica L. infusions were obtained with different infusion durations (5 or 10 min) or plant-to-water ratios (0.4, 1, or 2 g/100 mL). The hydrogels were characterized for stability by assessing the syneresis rate and textural and rheological attributes. To elucidate the influence of the infusion on the mechanisms of k-carragenan, temperature ramp tests were applied and FTIR spectra were acquired. Replacing water with Urtica dioica L. infusions for obtaining k-carrageenan hydrogels led to lower syneresis rates (3.34 ± 0.03% and 6.67 ± 0.33%), while the hydrogels showed increased hardness, but lower resilience and cohesiveness. The rheological parameters confirmed the reinforcement; higher G′ and gelling temperatures were registered compared to the reference. While FTIR spectra showed that the primary chemical backbone remained intact, the physicochemical changes indicate a strong physical synergy between nettle polyphenols and the κ-carrageenan chains. Of all samples, the highest antioxidant potential value of 94.66% was exhibited by the infusion obtained in 15 min with a ratio of plant material of 2/100 g. These findings demonstrate that plant-to-water ratios and infusion times are critical parameters for tuning the physical properties and biological efficacy of hydrogels for medical or food applications. Full article

The development of effective topical drug delivery systems remains a key challenge in wound management, particularly for bioactive compounds with limited skin permeability. In this study, a nanostructured bigel system incorporating sodium humate-loaded ultra-deformable vesicles (UDVs) was developed and evaluated for wound healing applications. Sodium humate-loaded UDVs were prepared using a thin-layer hydration method, and the influence of key technological parameters (phospholipid/glycerol concentrations, sonication time) on vesicle size and encapsulation efficiency was investigated. An optimized UDV formulation characterized by small particle size, high stability, and high drug encapsulation efficiency was selected and incorporated into a bigel composed of hydroxypropyl methylcellulose hydrogel and andiroba oil oleogel. The developed bigels were characterized in terms of microstructure, physical stability, pH, spreadability, and rheological behavior, demonstrating suitable properties for dermal application. In vivo wound healing evaluation in rat wound models revealed that bigels containing sodium humate-loaded UDVs significantly enhanced wound closure and tissue regeneration compared to control and reference treatments. Histopathological analysis confirmed improved granulation tissue formation and complete epithelialization. Overall, the results demonstrate that the proposed UDV-loaded hybrid bigel represents a promising nanostructured platform for enhanced dermal delivery and wound healing therapy. Full article

Biomaterials are engineered to interact with biological systems for therapeutic or diagnostic purposes. Among them, natural biomaterials offer important advantages over many synthetic polymers, including intrinsic biocompatibility, non-toxicity and biodegradability. Silk fibroin, a fibrous protein derived mainly from Bombyx mori cocoons, has re-emerged as a particularly versatile platform because it combines favourable mechanical, thermal, electrical and optical properties with aqueous processing and tuneable degradation. In this review, we first summarise the key structural, physicochemical and functional properties of regenerated silk fibroin, including its mechanical behaviour, thermal stability, dielectric and piezoelectric response, optical transparency and low autofluorescence. We then describe how extraction and regeneration protocols are used to produce defined material formats—fibres and nanofibrous mats, porous 3D scaffolds and hydrogels, sub-micron particles, thin films and microstructured devices—and outline major functionalisation strategies, ranging from physical blending and encapsulation to covalent chemistry, genetic engineering of recombinant silk variants, and enzyme-mediated conjugation approaches. Building on this foundation, we critically examine biomedical applications of silk fibroin with a particular emphasis on (i) hybrid silk–fluorophore systems for bioimaging and biosensing (nanodiamonds, quantum dots and organic dyes), (ii) optical fibre, wearable and edible sensors for health and food monitoring, (iii) wound dressings and wound-sensing platforms, and (iv) tissue engineering scaffolds and drug-delivery depots. Finally, we discuss current limitations, including process variability, the trade-offs introduced by blending and cross-linking, and the challenges posed by non-degradable inorganic fillers and clinical translation. Together, these perspectives highlight silk fibroin’s potential and constraints as a multifunctional biomaterial for next-generation biomedical devices and theranostic systems. Full article

Modeling immune cell recruitment within a wound-relevant microenvironment remains challenging. Here, we developed a novel skin-derived extracellular matrix (ECM) hydrogel model to study monocyte (THP-1) entry and phenotypic changes within a dermal fibroblast-populated (NHDF) matrix. The main novelty of this study is that it compares the effects of fibroblast-derived soluble signals and active monocyte infiltration in a 3D biomimetic model. Signaling by fibroblast-secreted soluble factors enhanced a pro-angiogenic secretome (e.g., >3-fold upregulation of VEGFA at day 1) and promoted endothelial tube formation (increasing network junctions to 1.16 ± 0.16 vs. 0.93 ± 0.23 in monoculture). In contrast, this paracrine signaling did not induce the matrix-driven pro-fibrotic response in hydrogels. Crucially, physical immune infiltration restricted monocyte penetration (mean depth of 8.92 ± 2.27 μm vs. 121.1 ± 15.9 μm in monoculture at day 5), reduced hydrogel-induced myofibroblast activation (decreasing α-SMA+ cells from 79.1% to 54.3% upon initial contact), and was associated with slower collagen loss during the early phase. (retaining a high-density collagen ratio of 3.46 ± 0.33 vs. 2.02 ± 0.29 in monoculture at day 1). These observations were accompanied by a shift toward a matrix-stabilizing profile, including increased TIMP expression and reduced pro-fibrotic markers. (ACTA2 and COL1A1). By including active immune infiltration (which was absent in previous tSVF models), we capture the transition from inflammation to the proliferation stage. Although the later stages of extensive ECM remodeling appear suppressed here, they may occur as repair progresses. Overall, our findings highlight that the immune cell is a key regulatory component for coordinating matrix preservation and vascular support. Importantly, this model replicates the early phases of wound healing, a stage where the monocyte–fibroblast secretome supports endothelial network formation. We established this innovative 3D ECM hydrogel system as a practical and physiologically relevant platform to investigate immune–matrix–stromal crosstalk. Full article

Hydrogels are endowed with exceptional hydrophilicity and biocompatibility by their network structure, while also exhibiting soft physical properties similar to living tissues, which renders them ideal biomaterials. Responsive hydrogels—particularly those constructed from multicomponent systems including proteins, polysaccharides, peptides, and polyphenols—have emerged as a frontier research focus owing to their tunable responsiveness and controllable functional properties. In this review, hydrogel response mechanisms were categorized according to pH, ionic strength, temperature, light, enzymes, and multi-stimuli interactions. Key preparation strategies, encompassing chemical, physical, and enzymatic crosslinking, were systematically introduced. The preparation of hydrogels from various food-grade matrices, such as polysaccharide-based, protein-based, peptide-based, and polyphenol-based systems, was also summarized, with emphasis placed on how their tailored structures govern functional performance. Furthermore, innovative applications of responsive hydrogels were highlighted, including targeted delivery of nutrients and bioactive substances (e.g., probiotics, anthocyanins, vitamins) in functional foods, smart packaging and sensing for real-time freshness monitoring of meat and fruits, food quality detection through colorimetric and photothermal sensors, and 4D food printing for personalized nutrition and dysphagia-friendly foods. Full article