Search Results (537)

The design of hydrogel-based materials for wound care management requires the integration of multiple functionalities, including the capacity to maintain hydration, to prevent infection, and to adapt to the dynamic wound microenvironment. In this study, we fabricated innovative pH-reactive multilayer hydrogel patches based on ionically crosslinked alginate and incorporated with bioactive compounds, including Manuka honey, hyaluronic acid, and Ribes nigrum extract. The multilayer structure is coated with chitosan to improve water affinity and pH response. The patches are designed to respond to variable pH conditions typical of wound environments, with potential applicability to burn wounds. The hydrogel materials are characterized in terms of water content, swelling behavior, and water vapor transmission rate (WVTR). The chitosan-coated multilayer hydrogel exhibited high water uptake (swelling ratio up to 22.11 ± 0.25; water content 95.48 ± 0.05%) and controlled WVTR (~3450–3850 g/m²·day⁻¹), while degradation remained below 42% at pH 8 compared to >80% in single layers. Microstructural analysis is performed via optical microscopy to assess the morphology and uniformity of the multilayer system, while chemical characterization is conducted using Fourier-transform infrared (FTIR) spectroscopy. The results highlight the ability of the designed material to respond to pH variations and to accommodate bioactive agents within a structurally stable and hydrated network, suggesting its suitability for future investigations into controlled release applications. Full article

The antibacterial properties of Ag(I) coordination compounds are well documented; however, their effectiveness is highly dependent on the choice of appropriate ligands, and it is frequently hindered by their low water solubility and limited bioavailability. Herein, six new Ag(I) complexes incorporating the quinazolinone thioamide mqztH (=2-mercapto-4(3H)-quinazolinone) and phosphine co-ligands were synthesized and investigated for their antibacterial activity. In vitro activity assays against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) bacterial strains revealed that all complexes selectively inhibited S. aureus bacterial growth. Structure–activity relationship analysis showed that monodentate PPh₃ co-ligands play a key role in enhancing the antibacterial efficacy of their complexes. Notably, complex [AgCl(mqztH)(PPh₃)₂] (1) exhibited broad-spectrum activity, with IC₅₀ values of 4.2 ± 1.4 μg mL⁻¹ (4.9 μΜ) for S. aureus and 63 ± 1.9 μg mL⁻¹ (75 μΜ) for E. coli bacteria. To improve solubility and antibacterial activity, complex 1 was encapsulated in barium alginate (BaAlg) matrices to form hydrogel-based drug delivery formulations [1]@BaAlg. The synthesized formulations retained the bactericidal effect of the complex, achieving comparable activity at concentrations lower by an order of magnitude compared to complex 1 in free form. Combined with the demonstrated high biocompatibility of complex 1 toward L929 normal eukaryotic cells, as well as the biocompatible nature of the alginate matrix, these findings underscore the strong potential of the complex 1-loaded hydrogel formulations for further investigation and development as effective antibacterial drug platforms. Mechanistic studies confirmed the redox-active nature of complex 1 and its potential to inhibit the function of glutathione reductase (GR) and thioredoxin reductase (TrxR) at low concentrations, suggesting the interference with bacterial redox homeostasis as a relevant mechanism of bioactivity. Full article

This paper proposes hybrid hydrogel insulin carriers based on alginate-hyaluronan (ALG/HA) and hydroxypropyl methylcellulose-hyaluronan (HPMC/HA) for topical application. The inclusion of insulin in a modern dressing can help restore metabolic balance and proper cell signaling in diseased tissue. Preformulation studies of the developed preparations were conducted, including analysis of the in vitro pharmaceutical availability of insulin, rotational and oscillatory rheology tests, and texture profile analysis. It was found that the developed insulin formulations provide an acceptable compromise between rheological and textural properties and ease of application, while ensuring prolonged release of the active substance. The results obtained provide a basis for further preclinical and clinical studies. Full article

This study is the first to encapsulate chicken broth into caviar-like hydrogel beads (CBHBs) using ionic gelation, aiming to explore their potential in molecular gastronomy and functional food design. The effects of calcium lactate concentration (1%, 2.5%, and 5%) and post-gelation holding time (0, 30, and 60 min) on the physicochemical, morphological, mechanical, and sensory properties of chicken broth hydrogel beads were evaluated. The beads were produced by dropping a 1% sodium alginate–chicken broth mixture into calcium lactate solutions, followed by analysis of diameter, bulk density, pH, color, shape, texture, and consumer acceptance. Results revealed that higher calcium concentrations and extended holding times significantly decreased bead diameter and increased bulk density and hardness, indicating denser and more compact structures. Morphologically, increased calcium levels resulted in irregular, droplet-like shapes, with reduced sphericity. Instrumental color analysis showed higher a*, b*, and chroma values at higher calcium levels. Sensory evaluations demonstrated that samples with lower calcium concentrations and no post-gelation holding were significantly preferred by panelists in terms of softness and overall liking. These findings underscore the importance of optimizing calcium concentration and holding time in the design of alginate-based hydrogel beads and suggest that CBHBs have potential applications in molecular gastronomy and functional food product development. Full article

Edible hydrogels are the central material class in 3D food printing because they reconcile two competing needs: (i) low resistance to flow under nozzle shear and (ii) fast recovery of elastic structure after deposition to preserve geometry. This review consolidates the recent years of progress on hydrogel formulations—gelatin, alginate, pectin, carrageenan, agar, starch-based gels, gellan, and cellulose derivatives, xanthan/konjac blends, protein–polysaccharide composites, and emulsion gels alongside a critical analysis of printing technologies relevant to food: extrusion, inkjet, binder jetting, and laser-based approaches. For each material, this review connects gelation triggers and compositional variables to rheology signatures that govern printability and then maps these to process windows and post-processing routes. This review consolidates a decision-oriented workflow for edible-hydrogel printability that links formulation variables, process parameters, and geometric fidelity through standardized test constructs (single line, bridge, thin wall) and rheology-anchored gates (e.g., yield stress and recovery). Building on these elements, a “printability map/window” is formalized to position inks within actionable operating regions, enabling recipe screening and process transfer. Compared with prior reviews, the emphasis is on decisions: what to measure, how to interpret it, and how to adjust inks and post-set enablers to meet target fidelity and texture. Reporting minima and a stability checklist are identified to close the loop from design to shelf. Full article

Hydrogels have emerged as promising biomaterials for oral tissue regeneration thanks to their high-water content, excellent biocompatibility, and ability to mimic native tissue environments. These versatile materials can be tailored to support cell adhesion, proliferation, and differentiation, making them suitable for repairing both soft and hard oral tissues. When engineered from natural polymers and enriched with bioactive agents, hydrogels offer enhanced regenerative potential. Biopolymer-based hydrogels, derived from materials such as chitosan, alginate, collagen, hyaluronic acid, and gelatin, are particularly attractive due to their biodegradability, bioactivity, and structural similarity to the extracellular matrix, creating an optimal microenvironment for cell growth and tissue remodeling. Recent innovations have transformed these systems into multifunctional platforms capable of supporting targeted regeneration of periodontal tissues, alveolar bone, oral mucosa, dental pulp, and dentin. Integration of bioactive molecules, particularly essential oils, bio-derived constituents, cells, or growth factors, has introduced intrinsic antimicrobial, anti-inflammatory, and antioxidant functionalities, addressing the dual challenge of promoting tissue regeneration while at the same time attenuating microbial contamination in the oral environment. This review explores the design strategies, material selection, functional properties, and biomedical applications in periodontal therapy, guided tissue regeneration, and implant integration of natural polymer-based hydrogels enriched with bioactive factors, highlighting their role in promoting oral tissue regeneration. In addition, we discuss current challenges related to mechanical stability, degradation rates, and clinical translation, while highlighting future directions for optimizing these next-generation bioactive hydrogel systems in regenerative dentistry. Full article

Chronic wounds remain a persistent clinical challenge due to delayed healing, recurrent infections, and limited effectiveness of conventional dressings. To address these unmet needs, we designed a multifunctional hydrogel system based on poly(vinyl alcohol) (PVA) and alginate (ALG), incorporating hyaluronic acid (HA)-loaded dipalmitoylphosphatidylcholine (DPPC) liposomes for regenerative stimulation and Aronia-mediated silver nanoparticles (Ag_Aro) for antimicrobial protection. Physicochemical analyses (DLS, SEM, FTIR) confirmed the successful assembly of the system and demonstrated distinct particle sizes, pore morphologies, and structural interactions. Swelling and degradation studies revealed favorable hydration capacity and stability under physiologically relevant conditions. In vitro assays with HaCaT keratinocytes indicated excellent biocompatibility, with HA-liposomes enhancing cell viability to ~190% and Ag_Aro showing minimal cytotoxicity, likely due to polyphenolic surface capping. The combined formulation achieved a balanced swelling profile, controlled degradation, and the highest biocompatibility (~195% viability), underscoring the synergistic benefits of the dual-agent design. This study introduces, to our knowledge, the first PVA–ALG bilayer hydrogel integrating HA-liposomes and phytosynthesized AgNPs, offering a promising platform for advanced wound management. Further in vivo studies are warranted to validate its therapeutic performance. Full article

Sodium alginate, a widely available and high-performance natural polymer, exhibits significant potential for applications in the biomedical field due to its excellent biocompatibility and versatile functionalization capabilities. This review systematically elucidates the fundamental properties and preparation methods of sodium alginate-based hydrogels, analyzing recent advancements in optimizing their mechanical properties, functionalization, and biological characteristics through strategies such as composite material construction, nano-reinforcement, and dynamic crosslinking. Furthermore, it summarizes the multifunctional applications of sodium alginate-based hydrogels in drug delivery, tissue engineering, and biosensing while addressing challenges in practical applications, including insufficient mechanical strength, regulating degradation rates, and maintaining stability in complex biological environments. To overcome these challenges, future research directions are proposed, including performance optimization, intelligent design, novel preparation techniques, and interdisciplinary collaboration, to facilitate the comprehensive transition of sodium alginate hydrogels from laboratory research to clinical applications. This review aims to provide a theoretical foundation and technical support for the fundamental research and biomedical applications of sodium alginate hydrogels while highlighting their promising prospects in addressing complex medical challenges. Full article

The natural wound healing process is often insufficient to restore tissue integrity in the case of chronic wounds, particularly when skin disruption is accompanied by pathological complications. The severity of these wounds is frequently exacerbated by persistent inflammation and the formation of bacterial biofilms, which significantly hinder skin regeneration. In this study, a pharmaceutical hydrogel-based wound dressing was developed and evaluated, incorporating silver nanoparticles synthesized with cinnamon essential oil that serves as both a stabilizer and antimicrobial agent, polymeric beta-carotene nanoparticles, and Centella asiatica extract. The work details the synthesis of both types of nanoparticles, their integration into an alginate-based matrix, and the subsequent formulation of composite dressings. The influence of each therapeutic agent on the morphology and structural characteristics of the dressings was demonstrated, along with the evaluation of their antimicrobial performance against both Gram-positive and Gram-negative bacterial strains. The antimicrobial effects observed within the first 24 h, critical for wound dressing application, highlight the potential of the developed materials for effective chronic wound management. A comprehensive set of analyses was performed to characterize the synthesized nanostructures and the final dressings. These included XRD, FTIR, SEM, EDS, and DLS. Additionally, swelling and degradation tests were conducted to assess hydrogel performance, while antimicrobial and antibiofilm activities were tested against Staphylococcus aureus and Escherichia coli over a 24-h period. The biocompatibility screening of the alginate-based wound dressings was performed on human keratinocyte cells and revealed that the incorporation of beta-carotene and Centella asiatica into alginate-based wound dressings effectively mitigates silver-induced cytotoxicity and oxidative stress and determines the development of highly biocompatible wound dressings. This paper presents an alginate hydrogel co-loaded with Ag nanoparticles, BC@PVP, and Centella asiatica extract that balances antimicrobial efficacy with cytocompatibility. Pairing silver with natural antioxidant/anti-inflammatory components mitigates cell stress while retaining broad activity, and the nanoparticle choice tunes pore architecture to optimize moisture and exudate control in chronic wounds. Full article

Electrokinetic (EK) remediation is a promising approach for the removal of heavy metals from fine-grained soils; however, its efficiency is often hindered by electrode polarization, pH imbalance, and ion accumulation. In this study, we developed a novel hydrogel-based electrode (NH electrode), composed of sodium alginate and multilayer graphene oxide (GO), to enhance the electrokinetic removal of Cu²⁺ and Pb²⁺ from loess. The electrode was systematically characterized by atomic force microscopy (AFM), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS), confirming its structural integrity, electrochemical activity, and interfacial conductivity. The NH electrode exhibited a smooth layered graphene structure with abundant oxygen-containing functional groups (AFM), negligible electrochemical polarization (CV), and low internal resistance with high conductivity (EIS), enabling efficient ion transport and adsorption. Electrokinetic tests revealed that the NH electrode outperformed conventional graphene (Gr) and electrokinetic graphite (EKG) electrodes. Single regulation strategies, including focusing position adjustment and electrode exchange, improved local removal efficiency by mitigating ion accumulation in targeted regions. The combined regulation strategy, integrating both measures, achieved the most uniform Cu²⁺ and Pb²⁺ removal, significantly suppressing hydroxide precipitation in cathodic zones and enhancing ion migration in the mid-section. Compared with literature-reported systems under similar or even more favorable conditions, the NH electrode and combined regulation approach achieved superior performance, with Cu²⁺ and Pb²⁺ removal efficiencies reaching 47.25% and 16.93%, respectively. These findings demonstrate that coupling electrode material innovation with spatial–temporal pH/flow field regulation can overcome key bottlenecks in EK remediation of heavy-metal-contaminated loess. Full article

In this study, the effect of cationic participation on the swelling behavior and pH-responsive release characteristics of polyelectrolyte hydrogel based on gelatin (Gel), sodium alginate (Alg), and carboxymethyl chitosan (CMCS) was explored. The shell–core morphology of the cationic coordination hydrogels was prepared by introducing Na⁺, Ca²⁺, and Fe³⁺ into the crosslinking system, which significantly altered the inherent pH-responsive swelling properties of Gel/Alg-CMCS hydrogel. The modified hydrogel demonstrated a release resistance of carvacrol (CAR) under acidic conditions while facilitating rapid release under neutral conditions. Notably, the CAR release profile was substantially modified by the distinct anti-swelling properties of cationic coordination hydrogels. In particular, Gel/Alg-CMCS-Fe³⁺ hydrogel exhibited high accumulative release of 58.34% at pH 1.0 while maintaining a minimal release degree of merely 7% in weakly acidic and neutral environments. These intriguing findings provide valuable insights into intelligent active delivery for future applications. Full article

Biofumigation was originally proposed as an alternative to toxic fumigants for the treatment of agricultural soils, owing to the biocidal effect of isothiocyanates (ITCs) released by some plant species like Brassicaceae. However, biofumigation also presents limitations; thus, an advanced and viable alternative could be the use of controlled-release systems such as gelled polymer networks. In the present work, we explore the use of biocompatible hydrogels based on sodium alginate (ALG) and sodium carboxymethylcellulose (CMC), conveniently loaded with a Brassicaceae extract for this purpose. The extract was characterized by means of HPLC-MS, showing its high glucosinolate content, especially glucoraphanin, a secondary metabolite produced by several species of this family. The physicochemical properties of the synthesized gels were investigated by means of differential scanning calorimetry (DSC), rheometry, and scanning electron microscopy (SEM), both in the presence and absence of the loaded extract. Loading and release kinetics (in water) were studied by means of HPLC-DAD, and the Weibull model was employed to interpret the results. It was found that both hydrogels can effectively confine the Brassicaceae extract’s active principle, slowly releasing it in an aqueous environment. Both systems possess excellent properties for real applications, with the CMC-based hydrogels being slightly preferable over the ALG ones due to their higher encapsulation efficiency, mechanical properties, and overall features. These systems are promising tools for combating harmful microorganisms due to the biocidal properties of glucosinolates, but their potential goes beyond their use in agriculture, as they could be applied as antifouling or antimicrobial agents in cultural heritage cleaning or other fields. Full article

This study aims to address the poor extensibility, brittleness, and limited hydration stability of pure sodium alginate (SA) hydrogels, which hinder their use in flexible, skin-adherent applications such as facial masks, by developing bio-based composites incorporating five representative functional additives: xanthan gum, guar gum, hydroxyethyl cellulose (HEC), poly(ethylene glycol)-240/hexamethylene diisocyanate copolymer bis-decyl tetradeceth-20 ether (GT-700), and Laponite^® XLG. Composite hydrogels were prepared by blending 1.5 wt% SA with 0.3 wt% of each additive in aqueous humectant solution, followed by ionic crosslinking using 3% (w/w) CaCl₂ solution. Physicochemical characterization included rotational viscometry, uniaxial tensile testing, ATR-FTIR spectroscopy, swelling ratio analysis, and pH measurement. Among them, the SA/XLG composite exhibited the most favorable performance, showing the highest viscosity, shear-thickening behavior, and markedly enhanced extensibility with an elongation at break of 14.8% (compared to 2.5% for neat SA). It also demonstrated a mean swelling ratio of 0.24 g/g and complete dissolution in water within one year. ATR-FTIR confirmed distinct non-covalent interactions between SA and XLG without covalent modification. The hydrogel also demonstrated excellent conformability to complex 3D surfaces, consistent hydration retention under centrifugal stress (+23.6% mass gain), and complete biodegradability in aqueous environments. Although its moderately alkaline pH (8.96) may require buffering for dermatological compatibility, its mechanical resilience and environmental responsiveness support its application as a sustainable, single-use skin-contact material. Notably, the SA/XLG composite hydrogel demonstrated compatibility with personalized fabrication strategies integrating 3D scanning and additive manufacturing, wherein facial topography is digitized and transformed into anatomically matched molds—highlighting its potential for customized cosmetic and biomedical applications. Full article

The development of advanced wound dressing materials with enhanced antibacterial properties is critical for improving patient outcomes and reducing infection risks. This study introduces a novel bio-based aerogel composed of copper-crosslinked alginate and hyaluronic acid, synthesized using supercritical gel drying techniques. Alginate and hyaluronic acid polymers are widely used in the pharmaceutical and medical industries because of their nontoxicity, biodegradability, and biocompatibility. This study aimed to create an aerogel that could be used as a potential wound dressing material by crosslinking hyaluronic acid and alginate with copper. The bio-based aerogel was prepared by ionic gelation and supercritical gel drying. The prepared materials were characterized using scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), BET surface area analysis, and energy-dispersive X-ray fluorescence (XRF). Moreover, the aerogel wound dressing properties were evaluated in terms of fluid uptake and antibacterial activity against S. aureus and E. coli. The physicochemical characterization of the prepared aerogels revealed their unique structural and morphological features, which are influenced by copper ion concentration and crosslinking time. Regarding their wound dressing evaluation, both aerogel and hydrogel were found to have antibacterial properties when tested on S. aureus with inhibition zones of (36 mm, 23 mm) and E. coli (31.6 mm, 21 mm) for hydrogel and aerogel, respectively. Also, excellent fluid uptake was found to reach up to 743%. These findings underscore the potential of copper-crosslinked alginate–hyaluronic acid aerogels as innovative wound dressing materials that combine superior antibacterial efficacy with excellent fluid management, paving the way for improved wound healing solutions. Full article

Hydrogel-based biosensors are commonly used in diagnostic applications. However, their performance remains constrained by slow analyte diffusion within polymer matrices, particularly when larger biomolecules are involved. Concave hydrogel geometries present a promising solution to enhance diffusion rates through increased surface area. However, the interfacial dynamics governing their formation must be studied. In this research, we investigated the interfacial dynamics that influence the formation of concave hydrogel discs fabricated by a simple pipetting method. We characterized the fluid interactions occurring during droplet deposition of alginate and CaCl₂ solutions. A three-phase flow model incorporating confocal microscopy validation was employed to simulate time-dependent interfacial behaviors. Concave hydrogel discs fabricated with alginate-first deposition exhibited 83% larger surface area compared to hemispherical counterparts at a CaCl₂: alginate volume ratio of one. Increasing the volume ratio further enhanced both surface area and diameter, though this highlighted limitations for microscopy-based detection. According to our results, reaction speed in alginate concave hydrogel discs can be controlled by varying the volume of CaCl₂ solution while keeping the volume of alginate solution constant, which changes the surface area while maintaining constant hydrogel volume. Full article