Composite Hydrogel Research Articles

Alginate@ Ag3PO4 Membranes Prepared with Different Crosslinking Agents and Their Photocatalytic Degradation of Dyes

Ag3PO4 has attracted attention for its excellent photoresponsive utilization and good catalytic performance. However, Ag3PO4 nanoparticles are prone to aggregation and difficult to recycle. In this paper, NaAlg@Ag3PO4 photocatalytic material were prepared in-situ growth method using NaAlg as a carrier. And the NaAlg@Ag3PO4 water solution was used as the casting solution. Three different crosslinking agents, oxalic acid (OA), CaCl2 and CuSO¬4, were used to crosslink NaAlg@Ag3PO4, resulting in three photocatalytic composite membranes, denoted as OA@NaAlg@Ag3PO4, CaAlg@Ag3PO4 and CuAlg @Ag3PO4. The prepared membranes were tested by infrared spectrum (IR), water contact angle and swelling properties in normal saline. The photocatalytic degradation performance of these membranes for simulated pollutant methyl orange (MO) was studied. The results showed that the composite membrane crosslinked by oxalic acid had good swelling resistance. The photocatalytic degradation performance of OA@NaAlg @Ag3PO4 hydrogel membrane was better than that of CaAlg@Ag3PO4 and CuAlg@Ag3PO4 membranes, and its reusability was the best. Compared with Ag3PO4 nanoparticles, the composite hydrogel photocatalytic membrane was easier to operate and recycle.

Research on the impact of polydopamine hydrogel electrodes with various doping methods on the performance of microbial fuel cells.

Microbial fuel cells (MFCs) have attracted considerable interest as a promising bioelectrochemical technology for directly converting chemical energy into electrical energy. However, their performance remains limited by the properties of anode materials and their interactions with microbial communities. In this study, PPy-MXene/PDA and PDA-PPy-MXene composite hydrogel electrodes (PMP and PPM) were fabricated on a conductive carbon felt substrate to systematically evaluate the influence of different PDA doping strategies on electrode performance. The PMP electrode exhibited a maximum power density of 3.62W/m2, which represented a 34.6% increase compared to the PPM electrode (2.69W/m2). Moreover, the protein content on the PMP electrode reached 38.05 ± 4.88mg/cm2, 3.79 times higher than that on the PPM electrode (10.05 ± 3.05mg/cm2). High-throughput sequencing of the 16S rRNA gene revealed that the relative abundance of Geobacter on the PMP electrode surface reached 73.66%, significantly higher than the 51.17% observed on the PPM electrode. These results are attributed to the PDA doping method involving secondary deposition on the electrode surface. This method optimizes the electron transfer pathways and significantly enhances the electrode's conductivity and electrochemical activity by altering the surface roughness of the electrode and increasing the content of hydrophilic functional groups. Consequently, it significantly promotes the enrichment of electroactive microorganisms and improves the efficiency of extracellular electron transfer. This study optimized PDA doping strategies to significantly enhance the electrochemical performance of MFCs, providing new insights and approaches for the rational design of high-performance bioelectrochemical electrodes.

Improvement of soybean protein isolate/konjac glucomannan-seaweed polysaccharide-based connective tissue simulants: effects of pH and water mobility on gel structure and gelling mechanism.

Improvement of soybean protein isolate/konjac glucomannan-seaweed polysaccharide-based connective tissue simulants: effects of pH and water mobility on gel structure and gelling mechanism.

A Robust and Tough Composite Hydrogel Electrolyte with Anion-Locked Supramolecular Network for Zinc Ion Batteries.

Hydrogel electrolytes have garnered extensive attention in zinc ion batteries due to their excellent flexibility and good safety. However, their limited mechanical properties, low ionic conductivity, and poor Zn2+ transference number pose significant challenges for developing high-performance zinc ion batteries. Herein, this work constructs a 3D supramolecular network capable of locking anions and active water molecules through the abundant hydrogen bonding interactions between aramid nanofibers, polyvinyl alcohol, and anions. This network synergistically enhances the mechanical properties (with a mechanical strength of 0.88MPa and a toughness of 3.28MJ m-3), ionic conductivity (4.22 S m-1), and Zn2+ transference number (0.78). As a result, the supramolecular composite hydrogel electrolyte can effectively inhibit dendrite growth and side reactions, facilitate interface regulation, and enable uniform zinc deposition. The Zn anode exhibits a cycle life of 1500h at 5mA cm-2 and 5 mAh cm-2, with an average coulombic efficiency of 99.1% over 600 cycles. Additionally, the Zn||polyaniline full cell maintains a high capacity retention of 78% after 9100 cycles at 1 A g-1. The assembled pouch cells demonstrate good flexibility, deformability, and compression resistance. This work provides valuable insights into the design of high-performance hydrogel electrolytes for zinc ion batteries.

Rheological characterization of a novel synergistic bovine serum albumin–xanthan gum composite hydrogel

Rheological characterization of a novel synergistic bovine serum albumin–xanthan gum composite hydrogel

Hydrogel Containing Bismuth Molybdate Nanosheets with Piezoelectricity and Nanoenzyme Activity for Promoting Osteoblast Responses.

The development of piezoelectric biomaterials with the capability to produce electrical signals and scavenge reactive oxygen species (ROS) is a novel strategy for stimulating osteoblast responses and promoting bone regeneration. Herein, tungsten (W), iridium (Ir), and ruthenium (Ru) codoped bismuth molybdate (4(W/Ru/Ir)-BMO) nanosheets with improved piezoelectricity and enzyme-like (CAT-like and SOD-like) activities were constructed by using the hydrothermal method. A composite hydrogel of oxidized sodium alginate/gelatin (OSA/GEL) and 4(W/Ru/Ir)-BMO (OSA/GEL/4-B) was also prepared. Due to the presence of 4(W/Ru/Ir)-BMO, OSA/GEL/4-B exhibited not only piezoelectricity but also enzyme-like activities. Under ultrasound (US), OSA/GEL/4-B generated electrical signals that significantly promoted the proliferation and osteogenic differentiation of bone marrow stromal cells. Furthermore, the piezoelectric effect of OSA/GEL/4-B improved the CAT-like (production of oxygen) and SOD-like (scavenger of ROS) activities. The improved piezoelectricity of 4(W/Ru/Ir)-BMO was attributed to the codoping of W, Ir, and Ru ions, which resulted in lattice distortion and enhanced crystal asymmetry, which produced electrical signals for regulating the osteogenic microenvironment. Moreover, the improvement of enzyme-like activities was attributed to the enhanced piezoelectric effect by the codoping of W, Ir, and Ru ions, which generated a piezoelectric field triggered by US that accelerated electron transfer for alleviating cellular oxidative stress and provided an antioxidant microenvironment for osteoblast responses. This piezoelectric hydrogel may provide a novel pathway for promoting osteogenic differentiation and bone regeneration.

Preparation and characterization of nano-silver/graphene oxide antibacterial skin dressing

This study aims to develop a composite hydrogel consisting of nano silver (Ag) and graphene oxide (GO) for use as a skin wound dressing. We prepared nanosilver/graphene oxide composite hydrogels by incorporating nanosilver and graphene oxide into kaolin-reinforced, gelatin-based hydrogels. Tests were conducted on the hydrogel’s water vapor permeability, mechanical properties, infrared warming performance and bacteriostatic properties under infrared light. The results indicated that kaolin enhanced the water vapor permeability and mechanical properties of the gelatin-based hydrogels. Moreover, the maximum fracture stress and strain of the hydrogel were elevated to 51.16 kPa and 1152.78% by GO, respectively. Furthermore, the modified Ag/GO hydrogels exhibited superior photothermal conversion and infrared bacteriostatic properties. This research offers valuable insights for the clinical repair of wounds and the design of new skin wound dressings, making these materials promising for such applications.

Bone Morphogenetic Protein-2-Derived Peptide-Conjugated Nanozyme-Integrated Photoenhanced Hybrid Hydrogel for Cascade-Regulated Bone Regeneration.

Critical-sized bone defects present a clinical challenge due to their limited self-repair capacity. Application of bone tissue-engineering scaffolds often overlooks the dynamic modulation of the microenvironment, resulting in unsatisfactory bone-regeneration outcomes. In this study, a bone morphogenetic protein-2-derived peptide-loaded honeycomb manganese dioxide (BHM) nanozyme was incorporated into a composite hydrogel (BHM@CG) composed of l-arginine-modified methacrylated carboxymethyl chitosan and gallic acid-grafted methacrylated gelatin. This hydrogel demonstrated a cascade-regulated enhancement of hemostasis, antibacterial activity, anti-inflammatory effects, and osteogenesis. Initially, the BHM@CG hydrogel achieved rapid hemostasis by quickly adhering to irregular defects upon injury. Subsequently, it displayed robust antibacterial activity through synergistic hydrogen bonding, hydrophobic interactions, and cationic interactions. Meanwhile, the BHM nanozyme and polyphenol groups from gallic acid effectively eliminated reactive oxygen species, enabling long-term inflammation regulation. Finally, sustained release of bioactive components promoted cell migration, angiogenesis, and osteogenesis, achieving a bone-formation rate of nearly 40% in a critical-sized calvarial defect model by week 8. More interestingly, the hydrogel also demonstrated efficient antibacterial and bone-regeneration capabilities in an infected critical-sized calvarial defect model. Overall, this hydrogel dynamically modulated the bone-defect microenvironment and effectively enhanced bone regeneration, offering a promising strategy for critical-sized bone-defect repair.

Injectable Gypsogenin‐Based Composite Hydrogel Enhances Osteoporotic Bone Regeneration by Alleviating Oxidative Injury via Promoting AMPKα Phosphorylation

AbstractOsteoporosis is characterized by an imbalance between osteoblasts and osteoclasts coupling and excessive oxidative stress in the bone microenvironment that impairs bone defect healing and increases the risk of non‐union. In this study, an injectable gypsogenin (GN)‐based organic–inorganic composite hydrogel (CCT/nHA@GN) is developed to treat osteoporotic bone defects. The hydrogel is made by grafting sodium citrate (SC) and nano‐hydroxyapatite (nHA)/GN nanoparticles onto carboxymethylated chitosan (CMCS). GN is a natural small‐molecule saponin, which shows biocompatibility and anti‐oxidant properties. The resulting hydrogel shows a well‐defined porous structure, favorable degradability, controlled drug‐release properties, and suitable rheological characteristics. Importantly, it reverses the differentiation fate of bone marrow‐derived mesenchymal stem cells (BMSCs) from osteoporotic patients and promotes angiogenesis in human umbilical vein endothelial cells (HUVECs). Furthermore, it activates the AMPKα‐FOXO3a‐CAT/MnSOD signaling pathway via AMPKα phosphorylation, thereby augmenting antioxidant stress capacity, promoting osteogenesis, inhibiting osteoclastogenesis, and ultimately rectifying the disrupted bone microenvironment. In vivo studies reveal that the bone volume to total volume (BV/TV) ratio of bones regenerated with the CCT/nHA@GN hydrogel is 2.85 times higher than that of the control group. In conclusion, these findings suggest that the injectable CCT/nHA@GN hydrogel can be a promising alternative material for the treatment of osteoporotic bone defects.

Preparation and Properties of 3D‐Printed Hydrogel‐Embedded PLA Composite Scaffolds

ABSTRACTThis study presents the development of a biodegradable composite scaffold designed to address the limitations associated with conventional bone repair materials. 3D‐printing filaments were developed using fish scale powder (FSP) or fish scale‐derived hydroxyapatite (HAP), polylactic acid (PLA), and polycaprolactone (PCL), with a focus on the optimal effect of 5 wt% HAP on the mechanical properties of PLA. Composite scaffolds were further prepared by integrating 3D‐printed grid scaffolds with chitosan/gelatin composite hydrogels through vacuum freeze‐drying. The properties of the composite scaffolds were evaluated through mechanical property tests, thermal analysis (including DSC and TGA), absorption rate assessments (conducted via immersion experiments in various solutions), and surface morphology analyses (utilizing SEM and EDS). The results show that the addition of HAP significantly improves the mechanical properties of 3D‐printed filaments. The high absorption rate exhibited by the HAP/PLA composite scaffold suggests improved biocompatibility and its potential for in vivo tissue fluid absorption. The HAP/PLA composite scaffold showed visible surface mineralization and degradation after 10 days of immersion in simulated body fluid (SBF), highlighting its potential for bone repair and regeneration.

Polyvinyl alcohol/casein hydrogels with oxymatrine eluting ability for cancer-related wound management.

Malignant fungating wounds (MFWs) are cancer-related complications that arise from metastases in advanced cancers. They appear in 5-14% of cancer patients, with higher prevalence in breast (66%) and head and neck (24%) cancers. Novel therapeutic routes for the management of MFWs rely on plant-based treatments, e.g. oxymatrine (OXM), an alkaloid derived from a Chinese plant with anticancer and anti-inflammatory properties. The objective of this work was to assess the potential of polyvinyl alcohol/casein (PVA/CAS) hydrogels to be used as dressings for OXM delivery. CAS can stimulate the immune system, while PVA is one of the most used synthetic polymers in the composition of hydrogels for medical applications. Six different hydrogel formulations were prepared following different procedures: freeze-thawing (FT) and cast drying (CD) for 24 or 48 h, with and without the addition of genipin (GE), a crosslinking agent. The hydrogels were loaded with OXM, and their release behaviour was studied. PVA/CAS-24CD + GE showed the best release profile. After being subjected to sterilisation by high hydrostatic pressure, it was further investigated in terms of physicochemical properties, mechanical characteristics and biocompatibility. Overall, this hydrogel revealed adequate characteristics to be used as a biocompatible medicated dressing for OXM release.

A Multifunctional Hydrogel for Infected Chronic Wounds Management: Integrated pH Sensing, Photothermal Therapy, and Ion Release

ABSTRACTChronic wound healing is often compromised by bacterial infection, and wound pH changes strongly correlate with infection. Therefore, the development of wound dressings capable of real‐time pH monitoring, antimicrobial activity, and tissue repair is crucial for the effective management of infected chronic wounds. This study reports a novel multifunctional composite hydrogel (GM‐C‐mBG@P) synthesized by incorporating microwave‐synthesized carbon quantum dots (CQDs) and polydopamine‐modified mesoporous bioactive glass nanoparticles (mBG@P) into modified gelatin methacryloyl (GelMA). The incorporated polydopamine (PDA) confers excellent photothermal properties to the hydrogel, enabling effective antimicrobial activity. Under 360 nm UV excitation, the fluorescence intensity of CQDs in GM‐C‐mBG@P exhibits a strong linear correlation with pH, enabling real‐time wound pH monitoring. Furthermore, mBG@P can gradually dissolve calcium, silicon, boron, and other functional ions to enhance the bioactivity and functionality of the hydrogel and accelerate wound healing. These findings suggest that the GM‐C‐mBG@P hydrogel has the potential to serve as a promising wound dressing for the treatment of infected chronic wounds.

Innovative Thermosensitive Composite Materials: Merging Poloxamer PF‐127 and Polysaccharides for Enhanced Functional Properties

AbstractCurrently, new cancer treatment options are being developed following tumor resection surgery, with a focus on minimizing invasiveness and reducing systemic toxicity to lower the risk of recurrence. In this context, the thermosensitive poloxamer Pluronic Acid F‐127 (PF‐127) is modified by incorporating polysaccharides with varying structures—xanthan gum (XG), alginate (ALG), gellan gum (GG), and levan (LEV). Hydrogels are synthesized using different ratios of polysaccharides and PF‐127. Rheological results reveal that adding polysaccharides to the hydrogel matrix increases storage moduli from 8 to 11–18 kPa and viscosity from 4.5 to 6.1–7.1 Pa s. Additionally, the micellar aggregation capacity (MAC) and gelation temperature shift from 34 °C to between 22 and 31 °C. Studies on 5‐fluorouracil (5‐FU) release from these composites indicate that enhanced MAC prolongs drug release 4 times longer compared to the hydrogel made with PF‐127 alone. A mathematical model is applied to analyze these experimental results, taking into account polymer chain release. Hydrogel's degradation rate and viscosity are primary determinants of drug release duration. Thus, by modifying the hydrogel composition, MAC, thermosensitivity, and drug release profile can be finely controlled based on the polysaccharide used.

Poly (vinyl alcohol)/carboxylated cellulose nanofibers composite hydrogel flexible strain sensors.

Poly (vinyl alcohol)/carboxylated cellulose nanofibers composite hydrogel flexible strain sensors.

Development of a bovine gelatin-kappa carrageenan-based dual network biomimetic hydrogel for chondrogenic differentiation of mesenchymal stem cells.

Development of a bovine gelatin-kappa carrageenan-based dual network biomimetic hydrogel for chondrogenic differentiation of mesenchymal stem cells.

Enhanced Compressive Strength of PVA/SA Composite Hydrogel by Highly Dispersed Hydroxyapatite Nanofibers

Rapid functional soft tissue restoration has shown considerable promise as a framework for stability and coordination in the human body. Inspired by the anisotropic arrangement of structures with soft and hard phases in biological tissues, such as tendon, cartilage, and ligament, many methods have been used to fabricate composite hydrogels with appropriate mechanical properties. The development of a high-strength hydrogel with strong bioactivity remains a key barrier to replace soft tissues with comparable synthetic structures. In this study, a highly dispersed hydroxyapatite nanofiber (HANF) reinforced polyvinyl alcohol-sodium alginate (PVA/SA) composite hydrogel is prepared for soft tissue replacement. The effect of the addition of HANF on the microstructure and properties of composite hydrogel is also investigated. The results show that the PVA/SA hydrogel, after the incorporation of HANF, combines well with the PVA/SA hydrogel (HANF@PVA/SA). SEM morphologies show that dispersed HANF can enter the holes of the three-dimensional structure of the composite hydrogel. Additionally, the addition of HANF can enhance the compressive strength of the PVA/SA composite hydrogel from 4.66 MPa to 7.72 MPa. At the same time, the HANF@PVA/SA hydrogel maintains the same excellent hydrophilicity as the original PVA/SA hydrogel. Finally, cytotoxicity and live/dead cell staining tests also confirmed its excellent biocompatibility, demonstrating its tremendous potential for use in soft tissue repair.

Interactions of Dialdehyde Bletilla striata Polysaccharide With Fibrin and Their Acceleration on Wound Healing

ABSTRACTOxidized polysaccharides have garnered significant attention as fillers for the development of reinforced composites, particularly in the biomedical field. In this study, we oxidized Bletilla striata polysaccharide (BSP) using sodium periodate to produce dialdehyde Bletilla striata polysaccharide (A‐OBSP). We then explored the potential of incorporating A‐OBSP into fibrinogen to create composite hydrogels. The inclusion of A‐OBSP notably altered the initial fibrin fibrillogenesis, resulting in more compact and organized fibrin networks. The storage moduli of the composite hydrogels were significantly higher than those of pure fibrin hydrogels. Furthermore, the presence of A‐OBSP enhanced water swelling and slowed the degradation of the hydrogels in phosphate‐buffered saline. The A‐OBSP‐enhanced composite hydrogels exhibited remarkable antibacterial, antioxidant, and anti‐inflammatory properties. In a murine wound healing model, the hydrogel containing 30 mg/mL A‐OBSP demonstrated superior wound healing efficacy compared to the pure fibrin group, as evidenced by the growth of hair follicles and capillaries in the granulation tissue, with a 100% healing rate by day 21. Additionally, the fibrin/A‐OBSP composite hydrogels showed significantly better therapeutic outcomes for wound healing than OBSP (TEMPO oxidation) and BSP, as reported in our previous studies. Therefore, fibrin/A‐OBSP composites hold substantial promise as wound healing dressings.

Tracking the Effect of Phosvitin (PV) Concentration on the Skin Permeation of Somatotropin (STH) from Semi-Solid Hydrogel Formulations.

Recombinant human growth hormone (rhGH) is utilized in pediatric patients with short stature for a variety of indications, including those in which the primary growth defect is not related to growth hormone deficiency (GHD). However, due to the instability of the hormone in the gastrointestinal tract and its short half-life, an alternative route of administration is being sought, which may be the skin. One strategy to extend the half-life of proteins involves the use of biodegradable polymeric matrices for transdermal drug delivery systems. While hydrogels are recognized for their high stability, the transport of proteins through the skin may be hindered. To address this, the use of active carriers is being investigated to enhance the efficiency of protein permeation through the skin. In this study, an effort was made to optimize the concentration of phosphitin (PV) as a carrier for somatotropin (STH). PV is a protein that possesses a distinctive cation chelating capability and amphiphilic character. As the concentration of PV increased, the rate of its emulsifying activity increased concomitantly. Methylcellulose (MC) was used as the hydrogel matrix. The study investigated three distinct concentrations of PV to ascertain the most optimal concentration to enhance STH availability. Following the formulation of hydrogel compositions containing STH and PV, the permeation process through porcine skin was examined using Franz's chambers. The findings revealed that the incorporation of PV significantly impacted both the penetration time of STH and the extent of STH penetration. Subsequently, an extensive evaluation of the physicochemical parameters of the formulations, encompassing pH, rheological, and textural properties, was conducted to assess their suitability for skin application. This evaluation aimed to ensure not only adequate persistence time of the formulation on the skin surface but also formulation stability and persistence of the active substance (STH).

High-Strength and Stretchable Fabric-Reinforced Hydrogel Composites: Their Applications on the Removal of Methylene Blue

Abstract The present paper reports a research for the preparation of the highly stretchable fabric-reinforced composite with enhanced mechanical properties. Removal of methylene blue (MB) from aqueous solution was studied using Cotton-polyvinyl alcohol (PVA) fibers woven fabric reinforced hydrogel composite with enhanced mechanical stability. The composite hydrogel comprised tetraethyl orthosilicate (TEOS) as the crosslinking agent. The morphology and properties of PVA/Cotton fabric reinforced hydrogel composites were characterized through Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimeter (DSC), thermogravimetric analyzer (TGA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Moreover, the electrochemical measurements of the MB were investigated using the differential pulse voltammetry (DPV) method, and the interaction between MB and TEOS-treated PVA/Cotton fabric was investigated using ultraviolet–visible (UV–vis) spectroscopy. Through this study, compared with the neat PVA/Cotton fabric breaking force in warp direction (664.74 N), increasing the TEOS ratio from 3% vol. to 100% vol. caused breaking force to increase properly to 22.37, 29.29, 64.04 and 72.27 N, respectively. The breaking force in weft direction decreased from 181.03 N (3% vol. TEOS concentration) to 138.77 N (10% vol. TEOS concentration) while it gradually increased from 225.65 (30% vol.) to 236.88 N (100% vol.). It can be concluded that PVA/Cotton fabric reinforced hydrogel composites with improved mechanical stability could be used as a potential adsorbent material to remove the MB dye from an aqueous solution.

Gamma radiation synthesis of a humidity sensor hydrogel based on superabsorbent of poly sodium acrylate and poly N -isopropylacrylamide copolymer loaded with CaCl 2 and charcoal

The primary objective of this research is to fabricate highly hydrophilic composite hydrogels to be used as a humidity sensor. A series of interpenetrating network copolymer hydrogels based on sodium acrylate (SA) and N -isopropylacrylamide (NIPAAm) monomers has been synthesized under the effect of gamma irradiation. The hydrogels were loaded with calcium chloride and charcoal as fillers. For comparison, hydrogels based on pure monomers were also synthesized. The pure hydrogels and composite hydrogels were characterized by different analytical methods such as gel content analysis, FT-IR spectra, swellability in water, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), water vapor uptake and humidity absorption. The results obtained indicated that the copolymer and composite hydrogels with CaCl 2 and charcoal Showed significant improvement in swellability in water, thermal stability and water vapour uptake and humidity absorption. The findings revealed also that the gel fraction is largely dependent on the irradiation dose and hydrogel composition. The addition of CaCl 2 and charcoal in the composite hydrogels strongly enhances the humidity absorption capacity of the dried gel and increases the humidity absorption capability in comparison to the hydrogels based on pure monomers.