Next Issue
Volume 12, May
Previous Issue
Volume 12, March
 
 
Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
7.6
5.3
Journals
Gels
Volume 12
Issue 4
share announcement

Gels, Volume 12, Issue 4 (April 2026) – 81 articles

Cover Story (view full-size image): This study presents novel photocrosslinked hydrogels based on methacrylated chitosan and methacrylated gelatin/allyl-modified gelatin and compares their properties as drug delivery systems in wound healing applications. Allylic gelatin-based hydrogels present larger pores and a stronger pH-responsive swelling behaviour, reflecting the higher flexibility of the 3D networks. The hydrogels release bacitracin during the first six hours, with a release profile that follows a non-Fickian diffusion mechanism. All formulated hydrogels exhibit antioxidant capacity and protein stabilization properties. The cytocompatibility, in vitro wound healing, and biological properties of the obtained hydrogels, as well as the drug release results, confirm their suitability in wound healing applications. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Section
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
13 pages, 1824 KB  
Article
Co-Immobilization of SpyTag-Cyclized Enzymes on a γPFD-SpyCatcher Hydrogel to Address Broad Specificity
by Ming-Yue Huang, Qing-Yi Su, Tao Wei and Fu-Xing Niu
Gels 2026, 12(4), 348; https://doi.org/10.3390/gels12040348 - 21 Apr 2026
Viewed by 223
Abstract
The broad substrate specificity of enzymes, while advantageous for catalytic diversity, often leads to undesired side reactions and reduced product yields in engineered metabolic pathways. To address this challenge, we developed a programmable protein scaffold based on a self-assembled γPFD-SpyCatcher hydrogel for the [...] Read more.
The broad substrate specificity of enzymes, while advantageous for catalytic diversity, often leads to undesired side reactions and reduced product yields in engineered metabolic pathways. To address this challenge, we developed a programmable protein scaffold based on a self-assembled γPFD-SpyCatcher hydrogel for the in vivo co-immobilization of SpyTag-cyclized cascade enzymes, enabling the co-immobilization of cascade enzymes in a spatially organized manner. Enzymes with broad substrate specificities were linearly fused with SpyTags, facilitating their spatial organization on the nanoscaffold within engineered E. coli to ensure directed catalytic flux. Using this strategy, the yields of pinene and caffeoyl-CoA were enhanced by 5.8-fold (reaching 94.5 mg/L) and 2.4-fold (reaching 78.6 mg/L), respectively, compared to free enzyme systems. This work establishes an effective approach to mitigate the limitations posed by broad enzyme specificity and demonstrates its potential for applications in synthetic biology and industrial biotechnology. Full article
(This article belongs to the Special Issue State-of-the-Art Gel Research in China)
►▼ Show Figures

Graphical abstract

22 pages, 3899 KB  
Article
A Multifunctional Shape-Adaptive Bilayer Hydrogel for Acute Hemostasis, Wound Repair, and Insect Bite Defense
by Rongyan He, Wenhui Yan, Qiuyu Cao, Chun Zhang, Yuxiu Ye, Yao Chen, Shaoxian Wu, Fei Han and Sulan Luo
Gels 2026, 12(4), 347; https://doi.org/10.3390/gels12040347 - 21 Apr 2026
Viewed by 368
Abstract
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 [...] Read more.
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
(This article belongs to the Special Issue Multifunctional Polymer Nano-, Micro- and Hydro- Gels: Synthesis, Properties and Applications (2nd Edition))
►▼ Show Figures

Graphical abstract

21 pages, 3575 KB  
Review
Advances in Gel-Based Electrolyte-Gated Flexible Visual Synapses for Neuromorphic Vision Systems
by Wanqi Duan, Yanyan Gong, Jinghai Li, Xichen Song, Zongying Wang, Qiaoming Zhang and Yuebin Xi
Gels 2026, 12(4), 346; https://doi.org/10.3390/gels12040346 - 21 Apr 2026
Viewed by 461
Abstract
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 [...] Read more.
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
(This article belongs to the Special Issue Advances in Gel Films (2nd Edition))
►▼ Show Figures

Graphical abstract

16 pages, 1976 KB  
Article
Surface Evolution and Visible-Light Photocatalytic Activity of Sol–Gel Derived Co3O4 Thin Films as a Function of Annealing Temperature
by H.I. Barragán-Méndez, Y.J. Acosta-Silva, S. Rivas, S. Gallardo-Hernández and A. Méndez-López
Gels 2026, 12(4), 345; https://doi.org/10.3390/gels12040345 - 20 Apr 2026
Viewed by 368
Abstract
Thin-film cobalt oxides have attracted increasing attention due to their visible-light activity and potential environmental applications. In this work, Co3O4 coatings were prepared on glass substrates through a sol–gel dip-coating process followed by thermal treatment at 450, 500, and 550 [...] Read more.
Thin-film cobalt oxides have attracted increasing attention due to their visible-light activity and potential environmental applications. In this work, Co3O4 coatings were prepared on glass substrates through a sol–gel dip-coating process followed by thermal treatment at 450, 500, and 550 °C. Structural characterization was carried out using X-ray diffraction (XRD) and Raman spectroscopy. Diffraction patterns, together with the Raman spectra, indicate the formation of the cubic spinel phase of Co3O4, while sharper diffraction peaks appeared at higher annealing temperatures, indicating improved crystallinity of the films. Surface morphology was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). SEM observations revealed continuous polycrystalline coatings, whereas AFM measurements showed clear variations in surface topography and roughness produced by thermal treatment. Wettability measurements obtained from contact angle (CA) analysis indicate modifications in the surface properties of the films as the annealing temperature changes. Optical characterization performed by ultraviolet–visible spectroscopy (UV–Vis) showed strong absorption in the visible region with an indirect band gap close to 1.58 eV. Photocatalytic activity was evaluated through the degradation of methylene blue under visible-light irradiation. Degradation efficiencies of approximately 93.9%, 97.4% and 98.7% were obtained after 5 h for films annealed at 450, 500, and 550 °C, respectively. Full article
(This article belongs to the Topic Advanced Nanomaterials and Technologies for Sustainable Development)
►▼ Show Figures

Figure 1

18 pages, 4936 KB  
Review
pH as a Design Tool for Low-Molecular-Weight Hydrogelators: Triggers, Structural Control, and Orthogonal Assembly
by Rie Kakehashi
Gels 2026, 12(4), 344; https://doi.org/10.3390/gels12040344 - 20 Apr 2026
Viewed by 387
Abstract
Low-molecular-weight gelators (LMWGs) have attracted growing attention as versatile alternatives to conventional polymeric thickeners and gelators, owing to their ability to form three-dimensional fibrillar networks through non-covalent self-assembly and to undergo reversible sol–gel transitions in response to external stimuli. Among the various stimuli [...] Read more.
Low-molecular-weight gelators (LMWGs) have attracted growing attention as versatile alternatives to conventional polymeric thickeners and gelators, owing to their ability to form three-dimensional fibrillar networks through non-covalent self-assembly and to undergo reversible sol–gel transitions in response to external stimuli. Among the various stimuli that can be exploited, pH represents a particularly attractive trigger given its direct relevance to biological and physiological environments. This review focuses on three categories of pH-responsive LMWGs that have shown notable progress over the past decade yet remain relatively underexplored in the literature. First, N-oxide-type hydrogelators are discussed, with emphasis on amide amine oxide-based surfactants and pyridine-N-oxide frameworks. The pH-dependent protonation of the N-oxide moiety modulates intermolecular hydrogen bonding, thereby governing self-assembly and gel formation. The structural versatility of these gelators enables rational tuning of aggregate morphology and confers clear pH and temperature responsiveness. Second, recent advances in phenylboronic acid-based LMWGs are highlighted. Although boronic acid derivatives have long been studied as dynamic crosslinking units in polymeric hydrogels, 3-isobutoxyphenylboronic acid was recently identified as the first example of phenylboronic acid functioning as an LMWG, in which gelation is driven primarily by hydrogen bonding and pH responsiveness is exploited for stimuli-triggered gel disruption rather than gel formation. Third, pH-responsive orthogonal self-assembly systems are reviewed. Representative examples include multicomponent hybrid hydrogels combining pH-activated LMWGs with polymer gelators for controlled drug release, pH-triggered self-sorting of two LMWGs without any polymeric component, and bio-based orthogonal hydrogels composed of a glucolipid LMWG and cellulose nanocrystals. For each system, both advantages and remaining limitations are critically assessed. Collectively, this review aims to provide a timely overview of emerging trends in pH-responsive LMWG research and to offer perspectives on the rational design of next-generation stimuli-responsive soft materials. Full article
(This article belongs to the Section Gel Processing and Engineering)
►▼ Show Figures

Graphical abstract

25 pages, 3065 KB  
Article
Enzyme-Loaded Liposomal Edible Hydrogel Films to Enhance Lactase Activity in Perline Mozzarella
by Esin Yilmaz, Ayse Avci, Elif Sezer, Muhammad Sohail Arshad, Zeeshan Ahmad and Israfil Kucuk
Gels 2026, 12(4), 343; https://doi.org/10.3390/gels12040343 - 20 Apr 2026
Viewed by 486
Abstract
Lactase enzyme-based products experience challenges including residual lactose that result in lactose intolerance. The purpose of this study was to develop polyelectrolyte polysaccharide-enriched lactase-encapsulated liposomal hydrogel films as an edible coating of Perline Mozzarella cheese that delivers enzymes along with the product on [...] Read more.
Lactase enzyme-based products experience challenges including residual lactose that result in lactose intolerance. The purpose of this study was to develop polyelectrolyte polysaccharide-enriched lactase-encapsulated liposomal hydrogel films as an edible coating of Perline Mozzarella cheese that delivers enzymes along with the product on the side of absorption in the small intestine. Coatings were investigated for shelf-life enhancement and in vitro enzyme release behaviour. Two different polymeric hydrogel film formulations were evaluated: lactase-encapsulated liposome-enriched chitosan (PCLLa) and lactase-encapsulated liposome-enriched polyelectrolyte chitosan and sodium alginate (CLLA). Lactase-encapsulated liposomes (mean particle size: 176 nm) were produced using 20% v/v lactase enzyme and 8% w/v lecithin using probe sonication. The edible hydrogel film coatings were applied on Perline Mozzarella cheese using the standard dip-coating method. Shelf-life characteristics of all samples were evaluated using pH, colour change, dry matter determination, microbial evaluation, and sensory analysis. CLLA coatings increased shelf life up to 60 days, displaying a pH of 5.48, continued normal colour, enhanced humidity balance, minimal bacterial growth, and the highest scores for sensory values when compared to both PCLLa (coatings) and the bare cheese substrate (control) samples. Furthermore, CLLA coatings provided greater stability for liposomes within the polyelectrolyte polymeric edible hydrogel film structure. Hence, the combination of liposomes with polyelectrolyte edible hydrogel films provides a novel strategy to enhance lactase enzyme encapsulation (for intolerance), stability, and delivering ability to the small intestine as well as improving the shelf life of coated cheese products. Full article
(This article belongs to the Topic Polymer and Biopolymer Nanocomposites for Emerging Medical, Industrial, and Environmental Applications)
►▼ Show Figures

Figure 1

20 pages, 3202 KB  
Article
In Vitro Digestibility and Structural Evaluation of Pea Protein-Based Emulsion-Filled Gels Designed for Dysphagia-Friendly Nutrition
by Ieva Bartkuvienė, Viktorija Eisinaitė, Evren Golge, Vilma Petrikaitė and Daiva Leskauskaitė
Gels 2026, 12(4), 342; https://doi.org/10.3390/gels12040342 - 19 Apr 2026
Viewed by 434
Abstract
This study examined the structural, rheological, and digestive properties of plant-based emulsion-filled gels (EFGs) formulated for dysphagia-friendly nutrition. EFGs were created using a pea protein–κ-carrageenan (PP–κ-CAR) matrix that incorporated oil droplets stabilized by pea protein (EFG-PP), soy lecithin (EFG-PP/LEC), or mono-/diglycerides (EFG-PP/MDG). All [...] Read more.
This study examined the structural, rheological, and digestive properties of plant-based emulsion-filled gels (EFGs) formulated for dysphagia-friendly nutrition. EFGs were created using a pea protein–κ-carrageenan (PP–κ-CAR) matrix that incorporated oil droplets stabilized by pea protein (EFG-PP), soy lecithin (EFG-PP/LEC), or mono-/diglycerides (EFG-PP/MDG). All formulations met the International Dysphagia Diet Standardisation Initiative Level 6 requirements and showed improved viscoelastic properties compared to the hydrogel control. The interfacial composition determined how the oil droplets influenced the gel network, with droplets in EFG-PP and EFG-PP/MDG contributing to greater reinforcement, whereas those in EFG-PP/LEC resulted in a weaker and more deformable structure. Among the formulations, EFG-PP/LEC demonstrated the most suitable properties for dysphagia management, including the lowest yield stress, softest texture, and highest protein hydrolysis (54%) and free fatty acid release (7.35 µmol/mL). These effects were associated with weaker oil–matrix interactions and greater enzymatic accessibility. The findings highlight the importance of interfacial design in tailoring EFG structure and digestibility for safe, energy-dense diets for individuals with dysphagia. Full article
(This article belongs to the Section Gel Processing and Engineering)
►▼ Show Figures

Figure 1

28 pages, 2481 KB  
Article
Efficacy of EPS Gel Coating and Lactic Acid Bacteria in Preserving Strawberry Postharvest Quality
by Dahiana Erazo Anacona, Daniela Neira Garzón, Anna María Polanía Rivera, Cristina Ramírez-Toro and German Bolívar Escobar
Gels 2026, 12(4), 341; https://doi.org/10.3390/gels12040341 - 19 Apr 2026
Viewed by 353
Abstract
Post-harvest economic losses in the strawberry industry are predominantly driven by disease caused by food-contaminating fungi and the loss of physicochemical quality. The gel-like matrix of the edible coating (EC) serves as a carrier for delivering lactic acid bacteria (LAB). This structured network, [...] Read more.
Post-harvest economic losses in the strawberry industry are predominantly driven by disease caused by food-contaminating fungi and the loss of physicochemical quality. The gel-like matrix of the edible coating (EC) serves as a carrier for delivering lactic acid bacteria (LAB). This structured network, characterized by its excellent adhesion and film-forming stability, maintains fruit integrity and delivers antifungal properties to control pathogens. This study tested an exopolysaccharide coating with L. plantarum A6 to assess its impact on strawberry shelf life and quality stored at 4 °C and 30 °C for eight days. Through the analysis of physicochemical properties, it was possible to observe that weight loss increased during storage time in all treatments except for strawberries coated (CF) at 4 °C, with 2.43 ± 0.2%. Regarding firmness, after 8 days of storage the greatest difference occurred in the fruit uncoated (UF) exposed to 30 °C decreased 30.93%, whereas the CF group showed a reduction of 2.04%, showing a significant difference between these treatments (p < 0.05). However, the CF at 4 °C had a value of 3.98 ± 0.3 N after eight days of storage, which is close to that of fresh fruit, indicating the effectiveness of the coating. In terms of microbiological results, the mesophilic and mold counts were lower in the treatment at 4 °C with coating (3.6 log CFU/g and 4.48 log CFU/g) than in the treatment stored at 30 °C (5.78 log CFU/g and 6.04 log CFU/g). The shelf-life estimate determined that CF stored at 4 °C could be preserved for 15 days and those stored at 30 °C for 6 days. Finally, sensory evaluation determined that CF stored at 4 °C were well-accepted in terms of attributes such as taste, sweetness, firmness, and flavor. These findings underscore the effectiveness of coating, not only in improving the storage quality of strawberries, but also in ensuring their sensory acceptance. Full article
(This article belongs to the Special Issue Functional Properties and Applications of Edible Gels)
►▼ Show Figures

Graphical abstract

20 pages, 4119 KB  
Article
Multiple-Dynamic-Bond Cross-Linked Injectable Antibacterial Hydrogel Sealants with Self-Healing for Wound Healing
by Tingting Wei, Yunrui Cao, Shuo Yang, Yu Song, Yanjun Liu, Hu Hou, Jie Xu and Changhu Xue
Gels 2026, 12(4), 340; https://doi.org/10.3390/gels12040340 - 19 Apr 2026
Viewed by 383
Abstract
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 [...] Read more.
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
(This article belongs to the Section Gel Chemistry and Physics)
►▼ Show Figures

Figure 1

25 pages, 3443 KB  
Article
Rheology-Guided and CFD-Integrated Analysis of Non-Isothermal Gelation Kinetics in a Three-Stage Cooling Die for Soy Protein Concentrate Extrusion
by Timilehin Martins Oyinloye and Won Byong Yoon
Gels 2026, 12(4), 339; https://doi.org/10.3390/gels12040339 - 17 Apr 2026
Viewed by 219
Abstract
Soy protein concentrate (SPC) undergoes continuous thermal and structural changes during passage through a cooling die, yet these changes are often interpreted using viscosity-based descriptions that do not explicitly account for structural development rate (SDR). This study developed a rheology-guided framework to analyze [...] Read more.
Soy protein concentrate (SPC) undergoes continuous thermal and structural changes during passage through a cooling die, yet these changes are often interpreted using viscosity-based descriptions that do not explicitly account for structural development rate (SDR). This study developed a rheology-guided framework to analyze SPC behavior in a three-stage cooling die by integrating isothermal and non-isothermal rheological characterization with computational fluid dynamics (CFD). SPC samples containing 76, 78, and 80% moisture were evaluated using strain sweep, frequency sweep, viscosity, time sweep, and temperature sweep tests. Lower moisture promoted stronger structure development, higher viscosity, and faster gelation. For the 76% moisture sample, peak SDR increased from 6.66 Pa/s at 50 °C to 22.46 Pa/s at 100 °C, while the time to peak decreased from 937 to 360 s. During non-isothermal cooling, the major structure development occurred in the 80–50 °C interval, where ΔG′ reached 4902.54 Pa at 76% moisture. CFD analysis showed that the gelation-kinetics-based model predicted both pressure and extrudate temperature more accurately than the viscosity-based model. Pressure RMSE ranged from 8.57 to 14.43 kPa for the kinetic model, compared with 11.31 to 22.39 kPa for the viscosity model. These results demonstrate that the three-stage cooling die should be interpreted as a coupled thermal, flow, and structure-development domain. Full article
(This article belongs to the Special Issue Design, Fabrication, and Applications of Food Composite Gels)
►▼ Show Figures

Graphical abstract

23 pages, 13695 KB  
Review
Review of Supramolecular Oleogel Lubricants
by Lei Wei, Minghui Xiong, Haoye Wang, Yuelin Chen, Song Chen and Jiaming Liu
Gels 2026, 12(4), 338; https://doi.org/10.3390/gels12040338 - 17 Apr 2026
Viewed by 354
Abstract
Supramolecular oleogel lubricants construct a three-dimensional network structure within base oils through gelator-mediated non-covalent interactions, such as hydrogen bonding, van der Waals forces, and π–π stacking. These materials demonstrate unique advantages in mitigating issues inherent to traditional lubricants, including leakage, volatility, creep, and [...] Read more.
Supramolecular oleogel lubricants construct a three-dimensional network structure within base oils through gelator-mediated non-covalent interactions, such as hydrogen bonding, van der Waals forces, and π–π stacking. These materials demonstrate unique advantages in mitigating issues inherent to traditional lubricants, including leakage, volatility, creep, and poor heat dissipation. Focusing on structural design and performance regulation, this review systematically summarizes the current development of supramolecular oleogel lubricants in the fields of green lubrication, extreme operating conditions, and nanocomposite lubrication. Specifically, it outlines the structure-property relationships between gelators and base oils in green lubrication systems, and elucidates the applications in radiation-resistant, high-load-bearing, and intelligently responsive lubrication. Strategies for utilizing nanocomposite supramolecular oleogels to resolve nanomaterial dispersion challenges are discussed, and the latest advancements in engineering applications are illustrated. By summarizing the development of supramolecular oleogel materials, this work can provide theoretical references for the future design and preparation of these lubricants. Full article
(This article belongs to the Section Gel Chemistry and Physics)
►▼ Show Figures

Figure 1

21 pages, 3484 KB  
Article
Design of Dipeptite-Based Organogelators as Separators of Cationic Dye Cyristal Violet from Water
by Gülşen Kaya, Mehmet Çolak, Halil Hoşgören and Necmettin Pirinccioglu
Gels 2026, 12(4), 337; https://doi.org/10.3390/gels12040337 - 17 Apr 2026
Viewed by 357
Abstract
The development of new advanced functional materials from low-molecular-weight gelators and their new potential applications have occupied a considerable place in research. The present study involves the design of dipeptide-based organogelators with enhanced hydrogen bonding network potentials and phase-selective capacities, possessing a minimum [...] Read more.
The development of new advanced functional materials from low-molecular-weight gelators and their new potential applications have occupied a considerable place in research. The present study involves the design of dipeptide-based organogelators with enhanced hydrogen bonding network potentials and phase-selective capacities, possessing a minimum gelation concentration of 0.2–0.4% w/v in different fluids. Seven new dipeptide organogelators were prepared based on a one-step reaction from two-component salt forms, the combination of Nε-alkanoyl-L-lysine ethyl ester with N-alkanoyl-L-amino acids (L-alanine, L-leucine, and L-phenylalanine), with high yields of up to 90. All the gel materials were extremely stable at room temperature, having a shelf life of several months, and formed gels in pharmaceutical fluids such as ethyl palmitate, ethyl myristate, and ethyl laurate, 1,2-propanediol, and liquid paraffin (oils widely used in pharmaceutical formulations), which meet the criteria of biological materials delivery. Their gelation properties were evaluated by rheological measurements. A very significant breakthrough in the current study is that organogels remove the toxic dye, crystal violet (CV), from water in a phase-selective manner with an extremely low gelator concentration. The dye and gelators are successively recovered via ethanol precipitation after the completion of the phase extraction process. Molecular dynamic calculations provide evidence for the 3D structures of the gels. Full article
(This article belongs to the Section Gel Chemistry and Physics)
►▼ Show Figures

Graphical abstract

23 pages, 2678 KB  
Article
Naringenin Nanocrystals Containing Pluronic® F127 Hydrogel for Skin Cancer Treatment
by Mayank Sharma, Neha Maheshwari and Rahul Maheshwari
Gels 2026, 12(4), 336; https://doi.org/10.3390/gels12040336 - 17 Apr 2026
Viewed by 405
Abstract
Naringenin (NRG), a poorly water-soluble flavonoid with anticancer potential, suffers from limited bioavailability due to low aqueous solubility and poor membrane permeation. In this study, NRG nanocrystals (NRG-NCs) were developed using an optimized antisolvent precipitation–probe sonication method and incorporated into a 20% ( [...] Read more.
Naringenin (NRG), a poorly water-soluble flavonoid with anticancer potential, suffers from limited bioavailability due to low aqueous solubility and poor membrane permeation. In this study, NRG nanocrystals (NRG-NCs) were developed using an optimized antisolvent precipitation–probe sonication method and incorporated into a 20% (w/w) Pluronic® F127 hydrogel for enhanced delivery. The optimized NRG-NCs exhibited a mean particle size of ~195 ± 5 nm, polydispersity index of ~0.20 ± 0.02, and zeta potential of −24 ± 3 mV. Percentage yield and drug loading capacity were 88.6 ± 2.3% and 78.4 ± 1.8%, respectively. Nanocrystal formation resulted in ~9-fold enhancement in saturation solubility compared to raw NRG. The NRG-NCs gel demonstrated rapid dissolution (~90% release within 120 min) and ~2.5-fold higher ex vivo permeation across the Strat-M® membrane relative to pure NRG. The hydrogel exhibited suitable physicochemical properties (viscosity ~12,850 cP; pH 6.2 ± 0.1; spreadability 5.8 ± 0.3 cm) and maintained >92% drug content after 30 days of refrigerated storage. Mechanistic studies revealed dose-dependent cytotoxicity, characterized by increased intracellular ROS, mitochondrial membrane depolarization, and elevated caspase-3 activity, confirming ROS-mediated apoptosis. In conclusion, the nanocrystal–hydrogel platform significantly enhances the solubility, permeation, and pro-apoptotic efficacy of NRG, demonstrating its potential for skin cancer treatment. Full article
(This article belongs to the Special Issue Design and Optimization of Pharmaceutical Gels (2nd Edition))
►▼ Show Figures

Figure 1

39 pages, 3122 KB  
Review
Designing Multifunctional Antibacterial Hydrogels: A Tri-Pillar Approach Based on Bacteriophages, Hydroxyapatite, and Electrospun Systems
by Jordi Puiggalí
Gels 2026, 12(4), 335; https://doi.org/10.3390/gels12040335 - 17 Apr 2026
Viewed by 477
Abstract
The rapid emergence of antibiotic-resistant bacteria represents one of the most critical challenges in modern healthcare and has stimulated intense research into alternative antimicrobial strategies. Antibacterial hydrogels have emerged as versatile biomaterials due to their high water content, tunable physicochemical properties, and ability [...] Read more.
The rapid emergence of antibiotic-resistant bacteria represents one of the most critical challenges in modern healthcare and has stimulated intense research into alternative antimicrobial strategies. Antibacterial hydrogels have emerged as versatile biomaterials due to their high water content, tunable physicochemical properties, and ability to function as multifunctional platforms for drug delivery and tissue regeneration. This review analyzes recent advances in antibacterial hydrogel systems through a conceptual framework based on three complementary pillars: biological antibacterial agents, inorganic functional components, and structural material engineering. Biological strategies, particularly bacteriophage-based approaches, provide highly specific antibacterial activity capable of targeting multidrug-resistant pathogens and disrupting bacterial biofilms. Inorganic components such as hydroxyapatite nanoparticles contribute additional functionalities including drug adsorption, modulation of the ionic microenvironment, and osteoconductive behavior relevant for bone-related infections. Structural design strategies based on electrospinning enable the fabrication of fibrous architectures that enhance mechanical stability, regulate therapeutic release, and mimic extracellular matrix organization. The integration of these three pillars within multifunctional hydrogel platforms offers promising opportunities for developing advanced antibacterial biomaterials capable of addressing infection control while supporting tissue regeneration. Full article
(This article belongs to the Special Issue Functionalized Hydrogels: Biomimetic Design, Adhesion Mechanisms and Biomedical Applications)
►▼ Show Figures

Graphical abstract

38 pages, 1991 KB  
Review
Thermal Conductivity in Nanoporous Aerogels: A Critical Review of Gas and Solid Conduction Models and Structure-Property Relations
by Rajesh Ramesh and Murat Barisik
Gels 2026, 12(4), 334; https://doi.org/10.3390/gels12040334 - 17 Apr 2026
Viewed by 765
Abstract
Sol–gel processing provides an unusually controllable route to nanoporous solids, making silica aerogels the leading reference systems for extremely low thermal conductivity due to their high porosity, nanoscale pore sizes, and tunable solid frameworks. Under near-ambient conditions, thermal transport is multi-scale and multiphase, [...] Read more.
Sol–gel processing provides an unusually controllable route to nanoporous solids, making silica aerogels the leading reference systems for extremely low thermal conductivity due to their high porosity, nanoscale pore sizes, and tunable solid frameworks. Under near-ambient conditions, thermal transport is multi-scale and multiphase, arising primarily from coupled solid conduction through the skeletal network and gas conduction within the pore space. Accordingly, aerogel design has emphasized suppressing solid-phase transport by reducing network connectivity, increasing tortuosity, and enhancing boundary scattering, while also limiting gaseous conduction through the control of pore size and gas pressure. This critical review provides an integrated overview of these mechanisms and the theory-to-experiment toolbox used to quantify the separate and combined contributions of the solid and gas phases to the effective thermal conductivity. We link key structural and environmental parameters (porosity, pore size distribution, density, backbone morphology, and pressure) to dominant transport regimes and the assumptions embedded in common models. Classical approaches, including effective-medium and percolation-based models, are assessed alongside phonon-scaling descriptions that incorporate characteristic length scales. Particular attention is given to the Knudsen effect and pressure-sensitive gas-conduction models, which are central to interpreting performance at atmospheric conditions and under vacuum or low-pressure operation. This review highlights inconsistencies across datasets and modeling practices, identifies persistent knowledge gaps, and outlines practical directions toward processable structure–property guidelines for manufacturing aerogels with targeted thermal performance, with regard to conduction-dominated heat transport mechanisms. Full article
(This article belongs to the Special Issue Recent Progress and Development of Advanced Aerogels: Latest Processing Methods, Improved Properties and Application (2nd Edition))
►▼ Show Figures

Figure 1

18 pages, 1953 KB  
Article
Cellulose Nanofibers Enhanced the Physicochemical Properties of Tannin Fe3+ Chitosan Composite Films for Tomato Preservation
by Panpan Feng, Jianguo Lin, Yan Ran, Yingying Zhang, Jiaxin Xu, Yuxin Cheng and Yuanyuan Liu
Gels 2026, 12(4), 333; https://doi.org/10.3390/gels12040333 - 16 Apr 2026
Viewed by 249
Abstract
To address inherent limitations of chitosan-based edible films, including inadequate mechanical strength and poor moisture resistance, cellulose nanofibers (CNF) were employed as a synergistic film-forming component to partially substitute chitosan in the fabrication of ternary composite films (denoted as CSTF-CNFs). This approach was [...] Read more.
To address inherent limitations of chitosan-based edible films, including inadequate mechanical strength and poor moisture resistance, cellulose nanofibers (CNF) were employed as a synergistic film-forming component to partially substitute chitosan in the fabrication of ternary composite films (denoted as CSTF-CNFs). This approach was based on a previously developed chitosan matrix modified with tannin-Fe3+ nanoparticles (TF). It was hypothesized that CNF could function as a reinforcing scaffold to improve the dispersion of TF within the film matrix and, through hydrogen bonding and physical entanglement, form an interpenetrating fiber network with chitosan, thereby enhancing the structural and barrier properties of the films. The present study systematically evaluated the influence of varying CNF substitution ratios (0–30%) on the physicochemical characteristics of the resulting composite films and their performance in tomato preservation. The results demonstrated that an appropriate CNF incorporation facilitated the formation of a dense, cross-linked network with chitosan and TF via hydrogen bond interactions, significantly improving both mechanical strength and water resistance. Among all formulations, the CSTF-CNF20 film exhibited optimal comprehensive performance, achieving the highest tensile strength of 27.60 MPa. Moreover, its swelling ratio markedly decreased from 675.5% (CSTF-CNF0) to 120.9%, while the water contact angle increased to 113.7°, and the DPPH radical scavenging activity remained above 85%. Tomato preservation assays revealed that, in comparison with the untreated control and polyethylene film-wrapped groups, the application of CSTF-CNF20 coating effectively mitigated the decline in weight loss and firmness, preserved surface color integrity, and resulted in the highest L* value alongside the lowest soluble solids content. These findings suggest that the synergistic integration of CNF with nano-scale metal–phenolic networks offers a viable strategy for developing high-performance chitosan-based edible films. The CSTF-CNF20 composite film holds significant promise for application in the postharvest preservation of fruits and vegetables. Full article
(This article belongs to the Special Issue Cellulose Gels: Preparation, Properties and Applications)
►▼ Show Figures

Graphical abstract

41 pages, 4107 KB  
Review
Recent Advances in Carbon Quantum Dot-Enhanced Stimuli-Sensitive Hydrogels: Synthesis, Properties, and Applications
by Mingna Li, Yanlin Du, Yunfeng He, Jiahua He, Du Ji, Qing Sun, Yongshuai Ma, Linyan Zhou, Yongli Jiang and Junjie Yi
Gels 2026, 12(4), 332; https://doi.org/10.3390/gels12040332 - 16 Apr 2026
Viewed by 272
Abstract
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 [...] Read more.
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
(This article belongs to the Special Issue Food Gel-Based Systems for Efficient Delivery of Bioactive Ingredients: Design to Application)
►▼ Show Figures

Graphical abstract

30 pages, 5100 KB  
Article
QbD Approach for Development of a Mucoadhesive Thermosensitive Gel for Oral Application: Risk Assessment Followed by Screening and Optimization
by Elena Dinte, Ioan Tomuță, Rareș Iuliu Iovanov, Tibor Casian, Ana Marcela Achim, Aranka Ilea, Adina Bianca Bosca and Horațiu Rotar
Gels 2026, 12(4), 331; https://doi.org/10.3390/gels12040331 - 16 Apr 2026
Viewed by 250
Abstract
The study aimed to develop a mucoadhesive thermosensitive buccal gel capable of forming an artificial clot after application in the extraction socket and providing prolonged release for metronidazole (MZ) and ibuprofen (IB). The critical quality attributes of the product were systematically evaluated using [...] Read more.
The study aimed to develop a mucoadhesive thermosensitive buccal gel capable of forming an artificial clot after application in the extraction socket and providing prolonged release for metronidazole (MZ) and ibuprofen (IB). The critical quality attributes of the product were systematically evaluated using Ishikawa (cause–effect) diagrams as a risk assessment tool, considering the factors related to the formulation, process, and methodology. Subsequently, Failure Mode and Effects Analysis (FMEA) was used to identify the critical parameters of the formulation and process characterized by a high probability of occurrence and a significant impact on product performance. The influence of qualitative and quantitative formulation variables was further investigated using two experimental designs, applied for both screening and optimization purposes. The rheological, adhesion, and in vitro release properties of the drugs were studied, and the optimized formulation for these characteristics contains Poloxamer 407 20.99% and HPMC K100M:K4M 1:1, 0.74%. The release of MZ and IB was prolonged over 8 h and followed Peppas’s kinetics. The optimized formula had an appropriate pH and an acceptable ex vivo mucoadhesion time. Stability studies revealed the preservation of mechanical properties and a recovery coefficient for MZ and IB of over 90%, after 12 months of storage. The optimized formula may be a potential candidate for the prevention of alveolar osteitis. Full article
(This article belongs to the Special Issue Polymeric Hydrogels for Biomedical Application (2nd Edition))
►▼ Show Figures

Figure 1

19 pages, 4964 KB  
Article
Freeze-Cast Chitosan/Resole Aerogels: Effect of Resole Fraction on Properties and Their Efficiency for Cr(VI) Uptake
by Jean Flores-Gómez, Milton Vázquez-Lepe, Álvaro de Jesús Martínez-Gómez, Víctor Hugo Romero-Arellano and Juan Morales Rivera
Gels 2026, 12(4), 330; https://doi.org/10.3390/gels12040330 - 15 Apr 2026
Viewed by 358
Abstract
Aligned CS/Rx aerogels were fabricated by inducing non-directional ice growth (freeze-molding) followed by low-temperature curing, resulting in monoliths with interconnected channels, a high void fraction, and moldability. The swelling index (S%) was calculated to be 1029, the apparent density 0.496 g·cm−3, [...] Read more.
Aligned CS/Rx aerogels were fabricated by inducing non-directional ice growth (freeze-molding) followed by low-temperature curing, resulting in monoliths with interconnected channels, a high void fraction, and moldability. The swelling index (S%) was calculated to be 1029, the apparent density 0.496 g·cm−3, and the estimated porosity 90% based on micrographic analysis. Aerogels have mechanical behavior Shore A hardness greater than 25. Batch metal removal tests were performed (10 mL, 100 mg·L−1 Cr(VI), 0.19 g adsorbent, 24 h, and pH 5–5.5), and the material achieved 95% metal removal. Additional kinetic and isothermal results were obtained using CS85R15 on a packed column (20 to 140 mg·L−1, 1000 mL Cr(VI), 0.80 g adsorbent, 24 h, and pH 5–5.5). Equilibrium data were consistent with a heterogeneous surface hosting a specific site, as reflected in the joint Freundlich/Langmuir fit (qmax 100.8 mg·g−1 for Langmuir). This confirmed the preservation of chitosan functionalities (–OH/–NH) after processing, while XPS detected chromium on the surface with signals consistent with the partial reduction of Cr(VI) to Cr(III) on the aerogel surface. This highlights the relevance of adsorption-based technologies for water remediation, where high-porosity and low-density materials allow for short diffusion pathways and capture electrostatics by protonated amines and redox conversion of hazardous substances. The soft-cure freeze-molding technique is simple, scalable, and compatible with packed-bed/column operation, providing a material platform for tailoring the microstructure (sheets and channels) and surface chemistry to regenerable sorbents for industrial wastewater treatment. Full article
(This article belongs to the Special Issue Recent Advances in Biopolymer Gels (2nd Edition))
►▼ Show Figures

Graphical abstract

19 pages, 4424 KB  
Article
A Chondroitin Sulfate–Iron Complex with Antibacterial Activity and Its Derived Hydrogel for Infected Wound Healing
by Qingshan Shen, Yujie Dong, Jiawen Li, Jiarui Wu, Chengzhi Hu, Yang Liu, Lei Zhao, Huan Zhan, Hua Bian and Yanli Ma
Gels 2026, 12(4), 329; https://doi.org/10.3390/gels12040329 - 15 Apr 2026
Viewed by 434
Abstract
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%. [...] Read more.
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
(This article belongs to the Section Gel Applications)
►▼ Show Figures

Graphical abstract

18 pages, 2725 KB  
Article
Ameliorative Effects of Liquiritin Carbomer Gel on Dinitrofluorobenzene-Induced Atopic Dermatitis in Mice
by Yun Zhang, Qiqing Tan, Sijia Li, Xiangdi Hu, Aoxiang Luo and Ming Li
Gels 2026, 12(4), 328; https://doi.org/10.3390/gels12040328 - 14 Apr 2026
Viewed by 509
Abstract
Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by dryness and itching. Steroids are the most common therapeutic agents, may induce skin atrophy, and damage the skin barrier. Therefore, we need to find a safer alternative option. Liquiritin (LQ), a flavonoid [...] Read more.
Atopic dermatitis (AD) is a chronic inflammatory skin disease characterized by dryness and itching. Steroids are the most common therapeutic agents, may induce skin atrophy, and damage the skin barrier. Therefore, we need to find a safer alternative option. Liquiritin (LQ), a flavonoid compound extracted from licorice rhizomes, possesses anticancer, anti-inflammatory, and antioxidant effects. This study aimed to investigate the therapeutic effects of LQ on AD, focusing on its potential skin barrier-protective and anti-inflammatory mechanisms. In this research, we prepared liquiritin carbomer gel (LQ-CG) and assessed its treatment effects on mice with AD triggered by 2,4-dinitrofluorobenzene (DNFB). It effectively attenuated AD progression by ameliorating skin lesions, decreasing epidermal thickness and mast cell infiltration, downregulating inflammatory cytokine levels, and restoring the expression of claudin-1, loricrin, and occludin. It also inhibited the release of TNF-α, IL-1β, and IL-6 in lipopolysaccharide (LPS)-stimulated RAW264.7 cells, and showed no significant toxicity to major organs in mice. In summary, our findings demonstrate that LQ-CG can effectively alleviate atopic symptoms by repairing the skin barrier and inhibiting inflammatory responses without causing significant changes in organ indices Full article
(This article belongs to the Special Issue Gels for Skin Treatment and Wound Healing)
►▼ Show Figures

Figure 1

23 pages, 5894 KB  
Article
Photothermal-Responsive Polyvinyl Alcohol/Gelatin/Graphene Oxide Hydrogels Loaded with Quercetin for NIR-Triggered Controlled Drug Delivery
by Alexa-Maria Croitoru, Tatiana Tozar, Mihai Boni, Angela Staicu, Roxana-Doina Trușcă, Bianca-Maria Tihăuan and Anton Ficai
Gels 2026, 12(4), 327; https://doi.org/10.3390/gels12040327 - 14 Apr 2026
Viewed by 547
Abstract
Photothermal therapy (PTT) has emerged as a promising medical strategy for controlled and targeted drug delivery, due to its ability to trigger rapid release while minimizing damage to surrounding environments. Among different near-infrared (NIR)-responsive nanomaterials, carbon materials are of particular interest due to [...] Read more.
Photothermal therapy (PTT) has emerged as a promising medical strategy for controlled and targeted drug delivery, due to its ability to trigger rapid release while minimizing damage to surrounding environments. Among different near-infrared (NIR)-responsive nanomaterials, carbon materials are of particular interest due to their multifunctional properties, with graphene oxide (GO) being a powerful photothermal therapy agent that can accelerate stimuli-responsive drug release. Herein, novel stimuli-responsive hydrogels based on polyvinyl alcohol (PVA), gelatin (Gel) and GO, loaded with natural quercetin (Q) were developed and evaluated for their physico-chemical properties, antibacterial and antifungal activities, photothermal Q release, and cellular metabolic activity. Upon NIR laser irradiation, after 10 min, Q was released twice as fast compared to conventional drug release without stimulation. The rapid release of Q by applying light radiation highlights the suitability of these hydrogels for controlled drug delivery applications. The PVA:Gel:GO/Q-hydrogels exhibited strong antimicrobial and antifungal performance (≥90% microbial reduction at higher GO concentrations). Furthermore, a significant reduction in S. aureus adhesion and invasion indicates the sample’s potential to mitigate bacterial infections. The PVA:Gel:GO/Q formulations exhibited high biocompatibility in Human Dermal Fibroblasts (HDF), demonstrating that Q improves the safety of PVA:Gel:GO-loaded hydrogels. These results offer promising potential for PVA:Gel:GO/Q hydrogels as advanced materials for photothermal-triggered drug delivery and antimicrobial applications. Full article
(This article belongs to the Special Issue Hydrogels in Biomedicine: Drug Delivery and Tissue Engineering)
►▼ Show Figures

Figure 1

25 pages, 3711 KB  
Article
Gelatin–Polyvinyl Alcohol Microspheres for Controlled and Sustained Release of BMP-2 and VEGF Enhance Osteogenic and Angiogenic Cell Differentiation
by Varvara Platania, Konstantinos Loukelis and Maria Chatzinikolaidou
Gels 2026, 12(4), 326; https://doi.org/10.3390/gels12040326 - 11 Apr 2026
Viewed by 602
Abstract
Bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) play a pivotal role in promoting osteogenesis and angiogenesis that concurrently take place during bone regeneration. The rapid degradation and diffusion of these growth factors, combined with the potential side effects associated with [...] Read more.
Bone morphogenetic protein-2 (BMP-2) and vascular endothelial growth factor (VEGF) play a pivotal role in promoting osteogenesis and angiogenesis that concurrently take place during bone regeneration. The rapid degradation and diffusion of these growth factors, combined with the potential side effects associated with their exogenous insertion, limit their applications. To overcome these shortcomings, we developed a controlled release system for BMP-2 and VEGF on microspheres comprising gelatin (Gel) and polyvinyl alcohol (PVA). We fabricated Gel–PVA microspheres using a constant Gel concentration of 10% w/v and a varied PVA concentration of 0, 5, and 10% w/v (Gel–PVA0%, Gel–PVA5%, and Gel–PVA10%, respectively). The microspheres were loaded with the model protein bovine serum albumin (BSA) first. The Gel–PVA10% microspheres demonstrated significantly higher loading capacity and encapsulation efficiency, as well as lower cumulative release rate, compared to the Gel–PVA5% ones when loaded with BSA. Thus, the microspheres with the Gel–PVA10% composition were selected for loading with BMP-2 and VEGF. Kinetic studies of BMP-2 and VEGF loaded into Gel–PVA10% microspheres indicated similar results to those with BSA. The microsphere concentration with the optimal cytocompatibility was 0.5 mg/mL, and it was applied for the assessment of the osteogenic differentiation using bone marrow-derived mesenchymal stem cells (MSCs), and for the angiogenic differentiation in Wharton jelly and adipose-derived MSCs. Alkaline phosphatase activity, collagen secretion, and calcium mineralization were significantly upregulated in the presence of BMP-2-loaded microspheres, while tubular formation and PECAM-1 secretion were significantly higher in VEGF-loaded microspheres compared to the unloaded control, demonstrating their effectiveness as drug delivery carriers. Full article
(This article belongs to the Special Issue Biofunctional Hydrogels for Biofabrication in Tissue Engineering)
►▼ Show Figures

Graphical abstract

17 pages, 2975 KB  
Article
Study on Synthesis and Performance of a Hybrid Crosslinked Composite Gel for High-Temperature Lost Circulation Control
by Jiangang Shi, Xuyang Yao, Chaofei Wang, Tao Ren, Kecheng Liu, Huijun Hao, Zhangkun Ren and Jingbin Yang
Gels 2026, 12(4), 325; https://doi.org/10.3390/gels12040325 - 11 Apr 2026
Viewed by 414
Abstract
Conventional chemical gel plugging materials often suffer from poor high-temperature stability and inadequate mechanical properties. To address these issues, this study developed a high-performance composite gel material using a multi-component hybrid crosslinking strategy. The material employs γ-methacryloxypropyltrimethoxysilane (MPTMS) as the silica source, which [...] Read more.
Conventional chemical gel plugging materials often suffer from poor high-temperature stability and inadequate mechanical properties. To address these issues, this study developed a high-performance composite gel material using a multi-component hybrid crosslinking strategy. The material employs γ-methacryloxypropyltrimethoxysilane (MPTMS) as the silica source, which hydrolyzes in situ to generate SiO2, thereby enhancing temperature resistance. Laponite nanoplatelets are incorporated as a toughening agent and physical crosslinking points, while a self-synthesized reactive microgel (BWL) serves as the organic crosslinking core. Through copolymerization with monomers such as acrylamide (AM) and methacrylic acid (MAA), a triple-crosslinked network structure is constructed. Compared with conventional gels, the synthesized hybrid crosslinked composite gel maintains a high storage modulus and loss modulus after aging at 140 °C and exhibits excellent tensile and compressive properties. Furthermore, the gel was processed into particle-based lost circulation materials with different particle sizes. High-temperature and high-pressure plugging experiments demonstrate that when using a mixed system of 40–60 mesh, 20–40 mesh, and 10–20 mesh gel particles with a total concentration of 2%, it can effectively seal highly permeable sand beds and fractures with apertures up to 5 mm. This meets the engineering requirements for lost circulation materials with high strength and high stability in deep, high-temperature formations. Full article
(This article belongs to the Topic Polymer Gels for Oil Drilling and Enhanced Recovery)
►▼ Show Figures

Graphical abstract

17 pages, 2695 KB  
Article
Short Eggshell Membrane Nanofibers–Chitosan Hydrogel with Dual-Functional Hemostasis and Shape Memory for Non-Compressible Wounds
by Shuang Zhao, Wei Jiang, Yating Gou, Shurui Zhu, Yutong Yuan, Biyun Li and Huihua Yuan
Gels 2026, 12(4), 324; https://doi.org/10.3390/gels12040324 - 10 Apr 2026
Viewed by 445
Abstract
Effective hemostasis in deep and irregular wounds remains a critical clinical challenge. To address this, we developed a bioresorbable chitosan composite hydrogel reinforced with short eggshell membrane (ESM) nanofibers, which were obtained through cryogenic grinding. The resulting ESM/CCS hydrogel, crosslinked with citric acid, [...] Read more.
Effective hemostasis in deep and irregular wounds remains a critical clinical challenge. To address this, we developed a bioresorbable chitosan composite hydrogel reinforced with short eggshell membrane (ESM) nanofibers, which were obtained through cryogenic grinding. The resulting ESM/CCS hydrogel, crosslinked with citric acid, exhibited significantly enhanced properties compared to pure CCS hydrogel, including a 63% increase in mechanical strength, a two-fold improvement in shape memory, a 25.31% reduction in hemolysis, over 2% higher cytocompatibility, and more than 48% greater hemostatic efficiency. Structural characterization confirmed the successful integration of bioactive chitosan with collagen mimetic ESM nanofibers. This biomimetic approach synergistically combines mechanical reinforcement with biological functionality, highlighting its strong potential as an advanced hemostatic dressing for complex wound management. Full article
(This article belongs to the Special Issue Nanocomposite Hydrogels for Drug Delivery and Wound Healing)
►▼ Show Figures

Graphical abstract

20 pages, 1588 KB  
Review
Cyclodextrin–Silica Hybrid PEG Hydrogels: Mechanistic Coupling Between Stiffness, Relaxation, and Molecular Transport
by Anca Daniela Raiciu and Amalia Stefaniu
Gels 2026, 12(4), 323; https://doi.org/10.3390/gels12040323 - 10 Apr 2026
Viewed by 345
Abstract
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 [...] Read more.
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
(This article belongs to the Special Issue Polymer Hydrogels and Networks)
►▼ Show Figures

Figure 1

19 pages, 2078 KB  
Article
Curcumin–Selenium Nanocomposites Integrated into Sol–Gel Siloxane Matrices for Antimicrobial and Delivery Applications
by Florentina Monica Raduly, Valentin Raditoiu, Alina Raditoiu, Iuliana Raut, Adriana Frone, Radu Claudiu Fierascu and Cristian-Andi Nicolae
Gels 2026, 12(4), 322; https://doi.org/10.3390/gels12040322 - 10 Apr 2026
Viewed by 421
Abstract
Selenium nanoparticles (SeNPs) represent promising bioactive agents due to their reduced toxicity and multifunctional biological properties. In this study, SeNPs were synthesized via an eco-friendly phytosynthesis approach using Curcuma longa extract, yielding curcumin-functionalized selenium nanoparticles (cur–SeNPs). The composites (cur–SeNPs), either in native extract [...] Read more.
Selenium nanoparticles (SeNPs) represent promising bioactive agents due to their reduced toxicity and multifunctional biological properties. In this study, SeNPs were synthesized via an eco-friendly phytosynthesis approach using Curcuma longa extract, yielding curcumin-functionalized selenium nanoparticles (cur–SeNPs). The composites (cur–SeNPs), either in native extract form or isolated, were incorporated into siloxane hybrid matrices prepared by the sol–gel method from tetraethyl orthosilicate: dimethyldimethoxysilane precursors, with polyvinylpyrrolidone (PVP) as a structural modifier. The host matrices were differentiated by the ratios between the precursors of the siloxane network, 3:1 for CS0–CS4, respectively, 1:1 for CS5, modified with PVP in the case of CS2 and CS3. These were loaded with cur–SeNPs–T in the cases of CS1, CS2, CS5 or with cur–SeNPs for CS3 and CS4. FTIR, XRD, SEM, and EDX analyses confirmed the formation of amorphous siloxane networks with well-dispersed SeNPs (up to ~12 wt%). PVP incorporation generated ordered mesoporous structures, increasing total pore volume sixfold and enlarging the average pore diameter to 9.26 nm. Studies about selenium ion release demonstrate that mesoporosity significantly enhances diffusion-controlled release. Antimicrobial assays against Staphylococcus aureus, Escherichia coli, and Candida albicans reveal a synergistic effect between curcuminoids and SeNPs, particularly in matrices with higher nanoparticle loading. The sol–gel technique for obtaining hybrid materials is very versatile regarding the supports on which the resulting materials or the compounds hosted in these host networks can be deposited. The dynamics of the development of hybrid materials is also reflected in the multitude of applications in various fields such as bio-medical, electronics, agriculture or food. Results obtained in this work highlight the potential of the developed systems for antimicrobial coatings on glass substrates and targeted delivery applications. Full article
(This article belongs to the Special Issue New Gels for Medical Applications)
►▼ Show Figures

Figure 1

26 pages, 3799 KB  
Review
Emerging Trends in Chitin-Based Hydrogels: From Fundamental Properties to Advanced Applications
by Merreta Noorenza Biutty, Ratri Puspita Wardani, Zeno Rizqi Ramadhan, Boram Yun, Achmad Yanuar Maulana, Jongsik Kim and Maulida Zakia
Gels 2026, 12(4), 321; https://doi.org/10.3390/gels12040321 - 9 Apr 2026
Viewed by 394
Abstract
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 [...] Read more.
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
(This article belongs to the Special Issue Hydrogels, Microgels, and Nanogels: From Fundamentals to Applications (4th Edition))
►▼ Show Figures

Graphical abstract

15 pages, 3175 KB  
Article
Preparation and Evaluation of MXene/Graphene-Integrated Cellulose Aerogel Composite for Self-Heating Thermoregulation in Athletic Warm-Up Optimization
by Xinran Qian, Lanqing Ling, Dengyun Xu, Jialu Lu, Haohan Liu, Meng Yuan, Tianfeng Lu, Lejun Wang, Ai Du and Lili Qin
Gels 2026, 12(4), 320; https://doi.org/10.3390/gels12040320 - 8 Apr 2026
Viewed by 402
Abstract
A warm-up is a critical procedure in sports science for enhancing muscular performance and optimizing subsequent athletic activities. However, the physiological and athletic performance effects of a warm-up are often transient, diminishing rapidly during the period of inactivity after the warm-up, which is [...] Read more.
A warm-up is a critical procedure in sports science for enhancing muscular performance and optimizing subsequent athletic activities. However, the physiological and athletic performance effects of a warm-up are often transient, diminishing rapidly during the period of inactivity after the warm-up, which is known as the warm-up transition phase. In this study, a multi-functional thermoregulation wearable composite film of graphene–MXene–bacterial cellulose/polyethylene glycol (G-M-BC/PEG) was developed by integrating MXene (a two-dimensional material with good photothermal conversion performance) and graphene into a bacterial cellulose aerogel framework, subsequently impregnated with polyethylene glycol (PEG-2000). The film showed stable structure, efficient solar photothermal conversion and storage (SPCS), and improved mechanical properties. Under 1 sun irradiation, the optimized G-M-BC/PEG wearable film showed excellent SPCS performance, sustaining a temperature plateau of 38–40 °C for 10 min after the xenon lamp was switched off under 1 sun irradiation, with a leakage rate of only 5.32% after five cycles. By constructing a biomimetic sports human body model, the composite aerogel was shown to significantly elevate muscle surface temperature and effectively mitigate heat loss during the transition phase. In the warm-up effectiveness and sports performance tests, the wearable film improved 200 m sprint performance by 0.8% ± 0.4% (p = 0.039). It also maintained subjective thermal sensation during the warm-up transition phase, with no significant decline at 5 or 10 min after the warm-up and a significant decrease only at 15 min (p = 0.02), while thermal comfort remained stable, suggesting improved neuromuscular readiness. This research provided a novel strategy for the fabrication of advanced aerogel-based wearable devices aimed at precision thermal management and athletic performance optimization. Full article
(This article belongs to the Special Issue Synthesis and Application of Aerogel (2nd Edition))
►▼ Show Figures

Graphical abstract

14 pages, 2711 KB  
Article
Comparison of Oleogels Obtained by Emulsion Template Method Using Low Molecular Weight Hydroxypropyl Methylcellulose (HPMC) with Fish and Vegetable Oils
by Alonso Escobar, Leticia Montes, Amaya Franco-Uría and Ramón Moreira
Gels 2026, 12(4), 319; https://doi.org/10.3390/gels12040319 - 8 Apr 2026
Viewed by 325
Abstract
This work evaluated the influence of oil type (sunflower vs. fish oil) and hydroxypropyl methylcellulose (HPMC) concentration on the properties of oleogels obtained by the emulsion-templated method. Oil-in-water emulsions were prepared and air-dried to produce oleogels containing 2.9–5.8% (w/w) [...] Read more.
This work evaluated the influence of oil type (sunflower vs. fish oil) and hydroxypropyl methylcellulose (HPMC) concentration on the properties of oleogels obtained by the emulsion-templated method. Oil-in-water emulsions were prepared and air-dried to produce oleogels containing 2.9–5.8% (w/w) HPMC. All oleogels exhibited solid-like behaviour, with viscoelastic moduli increasing with polymer concentration, and showed a high thermal stability. At a comparable HPMC content, fish oil oleogels developed stiffer networks than those obtained with sunflower oil. Texture analysis indicated a linear increase in hardness with HPMC content across both oils, while cohesiveness and adhesiveness were more influenced by oil nature. Oil-binding capacity (OBC) increased markedly with polymer content, exceeding 90% in most systems. However, fish oil oleogels consistently showed lower retention. Colour parameters were only slightly affected by HPMC concentration and were mainly determined by the intrinsic colour of each oil. Overall, both oil type and polymer concentration were shown to be critical factors determining the structural, mechanical, and functional characteristics of HPMC-based oleogels, providing useful information for the development of structured lipid systems as potential substitutes for conventional solid fats. Full article
(This article belongs to the Special Issue Oleogels, Bigels, and Emulgels: Fabrication, Application and Research Trends (2nd Edition))
►▼ Show Figures

Graphical abstract

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-81
Previous Issue
Next Issue
Back to TopTop