Gels | February 2026 - Browse Articles

25 pages, 4971 KB

Open AccessArticle

Synergistic Effects and Mechanisms of Plant Ash and Activator on Geopolymer Gel Formation, Hydration Evolution and Mechanical Properties

by Shoukai Chen, Yutong Tian, Jialin Chen, Hang Wang and Qingfeng Hu

Gels 2026, 12(2), 186; https://doi.org/10.3390/gels12020186 - 23 Feb 2026

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Abstract

Against the backdrop of promoting green buildings and a circular economy, the development of efficient, sustainable, and low-carbon cementitious materials is of great significance for reducing resource consumption and carbon emissions. In this study, plant ash (PA) was used as a partial cement [...] Read more.

Against the backdrop of promoting green buildings and a circular economy, the development of efficient, sustainable, and low-carbon cementitious materials is of great significance for reducing resource consumption and carbon emissions. In this study, plant ash (PA) was used as a partial cement replacement, and a series of alkali-activated composite cementitious materials (APAG) were prepared by regulating the dosages of PA and alkali activator (AA). The evolution of their workability, hydration behavior, and mechanical properties was systematically investigated. The results show that the incorporation of PA effectively delayed the setting process of the system; compared with P0, the initial and final setting times of P20 increased by approximately 302% and 100%, respectively, thereby mitigating the excessively rapid early-age reaction of the alkali-activated system while causing only a slight reduction in flowability. In contrast, the addition of AA shortened the setting time of APAG and led to a gradual decrease in fluidity. When the PA dosage was 20% and the AA dosage was 4%, APAG achieved a 28 d compressive strength of 57.8 MPa while maintaining good workability. Further analysis revealed a strong linear correlation between compressive strength and chemically bound water content under different PA and AA dosages, indicating that the reaction degree is a key factor governing macroscopic mechanical performance. Microstructural characterization confirmed that the incorporation of PA and AA significantly altered the reaction pathways and the morphology of hydration products, providing a reasonable microstructural explanation for the evolution of macroscopic properties. These findings provide valuable insights into the high-value utilization of biomass waste and the broader application of green cementitious materials. Full article

(This article belongs to the Section Gel Chemistry and Physics)

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16 pages, 2786 KB

Open AccessArticle

Perfusion-Limited Efficacy of Platelet-Rich Plasma in Adipose Tissue Grafts

by Hanan Jamal Mohamed, Wonwoo Jeong, Jiwon Choi, Min Kyeong Kim, Jonghyeuk Han and Hyun-Wook Kang

Gels 2026, 12(2), 185; https://doi.org/10.3390/gels12020185 - 22 Feb 2026

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Abstract

Autologous adipose tissue (AT) grafting is often compromised by insufficient early vascularization, leading to ischemia, fibrosis, and inconsistent long-term volume retention. Incorporating platelet-rich plasma (PRP) into AT bioinks offers a clinically accessible means to enhance vascular recruitment, but the in vivo impact of [...] Read more.

Autologous adipose tissue (AT) grafting is often compromised by insufficient early vascularization, leading to ischemia, fibrosis, and inconsistent long-term volume retention. Incorporating platelet-rich plasma (PRP) into AT bioinks offers a clinically accessible means to enhance vascular recruitment, but the in vivo impact of PRP dosage remains unclear. Here, we investigated how PRP concentration, uniformly integrated into a previously reported clinically relevant AT bioink, regulates vascular infiltration, tissue remodeling, and overall graft survival. High-dose PRP markedly improved graft performance, including an 8-fold increase in highly perfused regions, a 3.8-fold enhancement in adipocyte survival, a 1.67-fold reduction in fibrosis, and a 2.51-fold increase in collagen III deposition compared with PRP-free AT grafts. Histological analysis further demonstrated that PRP mitigates the adverse effects of poor perfusion, reducing regional disparities in survival and extracellular matrix (ECM) remodeling. High-dose PRP also maximized graft retention, preserving 103% of graft mass relative to 50.6% in native AT. Together, these results establish a clear in vivo dose–response relationship for PRP-enhanced AT grafts and highlight platelet concentration as a key design parameter for soft-tissue reconstruction. This work provides a translational framework for optimizing PRP-functionalized bioinks to improve clinical outcomes in reconstructive surgery. Full article

(This article belongs to the Special Issue Advanced Hydrogels for Tissue Engineering and Drug Delivery (2nd Edition))

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24 pages, 4277 KB

Open AccessArticle

Gel-Inspired Trapping Networks: Fe(III)-Activated Palygorskite Nanorod Aggregates for Enhanced Congo Red Sequestration

by Hao Chen and Yufan Song

Gels 2026, 12(2), 184; https://doi.org/10.3390/gels12020184 - 22 Feb 2026

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Abstract

Developing adsorbents that combine high capacity with structural robustness remains a critical challenge for dye wastewater treatment. In this study, we propose a “pollutant-induced gelation” strategy to address this limitation, using Fe(III)-activated palygorskite nanorod aggregates as a model system for the highly efficient [...] Read more.

Developing adsorbents that combine high capacity with structural robustness remains a critical challenge for dye wastewater treatment. In this study, we propose a “pollutant-induced gelation” strategy to address this limitation, using Fe(III)-activated palygorskite nanorod aggregates as a model system for the highly efficient sequestration of Congo red (CR). Unlike conventional modification methods that rely solely on surface functionalization, this approach leverages the adsorbed dye itself as a synergistic assembly promoter. The addition of CR significantly consolidates the Fe(III)-mediated aggregation of palygorskite nanorods, leading to the formation of an integrated three-dimensional porous network with distinct gel-like rheological behavior. This dye-induced gel network not only provides abundant confined spaces for pollutant entrapment but also enhances the structural integrity of the adsorbent, facilitating separation and potential reuse. Compared to pristine palygorskite, the Fe(III)-activated material exhibited a 95.4–277% increase in adsorption capacity across a pH range of 4–10. The adsorption process followed pseudo-second-order kinetics and the Temkin isotherm model, and was thermodynamically spontaneous and exothermic. Mechanistic studies revealed a synergistic interplay: Fe(III) served as primary cross-linking nodes to construct the network framework, while CR molecules acted as inducers to reinforce the gel architecture, enabling strong physical immobilization of dye aggregates. This work provides a new paradigm for designing intelligent, gel-based adsorbents from natural nanoclays, transforming a pollutant into a structural promoter. Full article

(This article belongs to the Special Issue Advanced Functional Gels: Design, Properties, and Applications)

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20 pages, 3029 KB

Open AccessArticle

Sustainable Date Palm Biomass Hydrogel Improves Soil Hydro-Physical Properties and Tomato Growth Under Arid Conditions

by Gamareldawla H. D. Agbna and Syed Javaid Zaidi

Gels 2026, 12(2), 183; https://doi.org/10.3390/gels12020183 - 22 Feb 2026

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Abstract

Water scarcity, rapid soil moisture loss, and high evaporative demand severely limit vegetable production in arid regions such as Qatar. Sustainable soil amendments that enhance water retention and stabilize plant water status are therefore critical for improving productivity. This study evaluated a biodegradable [...] Read more.

Water scarcity, rapid soil moisture loss, and high evaporative demand severely limit vegetable production in arid regions such as Qatar. Sustainable soil amendments that enhance water retention and stabilize plant water status are therefore critical for improving productivity. This study evaluated a biodegradable hydrogel synthesized from date-palm leaf cellulose using a sodium alginate crosslinking method and assessed its effects on soil hydro-physical properties and tomato (Solanum lycopersicum L.) performance under arid conditions. A pot experiment was conducted under semi-controlled conditions using a single-factor randomized complete design with three hydrogel rates (0, 1, and 2% w/w) and three replications, with one plant per pot. All treatments received the same seasonal irrigation depth, scheduled when soil moisture declined to approximately 60–65% of field capacity. The hydrogel exhibited rapid hydration behavior, reaching equilibrium within 30–60 min with a swelling ratio of 5.659 g g⁻¹, corresponding to a water uptake of 465.9%, and SEM analysis revealed a porous internal structure favorable for water retention. At 1 and 2% application rates, hydrogel significantly reduced bulk density, increased total porosity and field capacity, and maintained higher soil moisture across irrigation cycles. Tomato plants grown in hydrogel-amended pots showed substantial gains in fresh biomass and root length, together with higher chlorophyll content, leaf nitrogen concentration, and relative water content. Water use efficiency improved significantly at 1% hydrogel, whereas the 2% rate showed a positive but non-significant trend. Overall, the results demonstrate that hydrogels derived from date-palm waste can enhance soil water retention, plant physiological status, and tomato productivity, offering a locally relevant strategy to improve agricultural resilience in arid environments. Full article

(This article belongs to the Special Issue Biomass-Based Gels)

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60 pages, 10848 KB

Open AccessReview

Alginate-Based Hydrogels: Recent Progress in Preparation, Property Tuning, and Multifunctional Applications

by Xiaoxu Liang, Shiji Chen, Yuxiong Liang, Miaomiao Wang, Qiao Wang, Dexin Chen, Xiao Ma, Hongyao Ding and Hai-Jing Zhong

Gels 2026, 12(2), 182; https://doi.org/10.3390/gels12020182 - 21 Feb 2026

Cited by 1 | Viewed by 199

Abstract

Alginate-based hydrogels, derived from brown seaweed, represent biocompatible and biodegradable materials whose properties are systematically controlled through molecular structure (M/G composition), crosslinking strategy, and compositional modification. This review synthesizes recent advances in alginate hydrogel design, encompassing fundamental structural properties, three primary crosslinking approaches—ionic [...] Read more.

Alginate-based hydrogels, derived from brown seaweed, represent biocompatible and biodegradable materials whose properties are systematically controlled through molecular structure (M/G composition), crosslinking strategy, and compositional modification. This review synthesizes recent advances in alginate hydrogel design, encompassing fundamental structural properties, three primary crosslinking approaches—ionic coordination with divalent cations (Ca²⁺, Ba²⁺, Sr²⁺), covalent chemical linkages, and hybrid multi-crosslinking systems—and strategic modification strategies including chemical derivatization, polymer blending, and nanoparticle incorporation. These modifications address inherent limitations of native alginate, namely insufficient mechanical strength and biological inertness, thereby expanding applicability. The review examines applications across biomedical domains (drug delivery, tissue engineering, wound healing), environmental remediation, food industry systems, and emerging technologies including flexible electronics and soft robotics. Advanced fabrication techniques—3D/4D printing, microfluidics, and electrospinning—enable improved architectural control. Current evidence from preclinical and clinical studies demonstrates feasibility in specific applications, while important challenges persist, including predictable degradation kinetics, mechanical property optimization, standardization of characterization protocols, regulatory compliance, and manufacturing scalability. This review aims to provide a systematic assessment of alginate-based hydrogel development and identify areas requiring further investigation to advance clinical translation. Full article

(This article belongs to the Special Issue Smart Gels for Sensing Devices and Flexible Electronics)

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23 pages, 6187 KB

Open AccessArticle

Design and Optimization of Thermosensitive Hydrogels Combined with Lipid Nanotechnology for Topical Curcumin Application

by Daniela Vergara, Benjamín Vega, Claudia Sanhueza, Mariela Bustamante, Francisca Acevedo and Olga López

Gels 2026, 12(2), 181; https://doi.org/10.3390/gels12020181 - 20 Feb 2026

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Abstract

A novel co-encapsulation platform based on curcumin-loaded liposomes (Cur-Lip) incorporated into thermosensitive hydrogels (TSH) was developed to address the physicochemical and biological limitations of topical curcumin (Cur) delivery. Response Surface Methodology (RSM) was used to optimize Pluronic^® F-127, glycerol, and alginate concentrations [...] Read more.

A novel co-encapsulation platform based on curcumin-loaded liposomes (Cur-Lip) incorporated into thermosensitive hydrogels (TSH) was developed to address the physicochemical and biological limitations of topical curcumin (Cur) delivery. Response Surface Methodology (RSM) was used to optimize Pluronic^® F-127, glycerol, and alginate concentrations with respect to gelation time and viscosity. The optimized formulation (22% Pluronic^® F-127, 5% glycerol, and 0.5% alginate) exhibited rapid time sol–gel transition (~86 s), suitable viscosity (~377 mPa·s), excellent model fitting (R² = 0.99) and prediction accuracy. Three formulations (TSH, Cur-TSH, and Cur-Lip-TSH) were subsequently prepared and displayed appropriate thermoresponsive behavior. The Cur-Lip system showed high encapsulation efficiency (~78%). Upon incorporation into the TSH, Cur-Lip-TSH displayed increased viscosity and mechanical strength at physiological temperature. In vitro studies confirmed its cytocompatibility toward human keratinocytes, significant antibacterial activity against Staphylococcus aureus, Staphylococcus epidermidis, and Pseudomonas aeruginosa, and no irritation potential as assessed by the Hen’s Egg Test on the Chorioallantoic Membrane assay (HET-CAM). Overall, Cur-Lip-TSH represents a safe and robust thermosensitive platform that provides a foundation for future studies on controlled curcumin release and topical performance. Full article

(This article belongs to the Special Issue Liposomal and Ethosomal Gels: From Design to Application (2nd Edition))

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13 pages, 4687 KB

Open AccessArticle

Effects of CaCO₃/NaHCO₃ on Porous Structure and Quality Characteristics of Protein–Starch Gel Network Formed via Extrusion

by Feng Guo, Huan Zhou, Hui Hu, Anna Hu, Qiang Wang and Jinchuang Zhang

Gels 2026, 12(2), 180; https://doi.org/10.3390/gels12020180 - 20 Feb 2026

Viewed by 132

Abstract

CaCO₃ and NaHCO₃, respectively serving as chemical leavening agents, can promote the expansion of protein or starch extrudates, thereby forming a porous structure. However, the characteristics of this porous structure under the combined regulation of CaCO₃ and NaHCO₃ [...] Read more.

CaCO₃ and NaHCO₃, respectively serving as chemical leavening agents, can promote the expansion of protein or starch extrudates, thereby forming a porous structure. However, the characteristics of this porous structure under the combined regulation of CaCO₃ and NaHCO₃ remained unclear. The results indicated that increasing the proportion of NaHCO₃ promoted the expansion of the extruded protein–starch gel network, with its expansion ratio significantly increasing from 2.29 to 3.17 (p < 0.05). This expansion resulted in larger pores, which corroborated the observed significant increase in water holding capacity (WHC). Conversely, an increase in the proportion of CaCO₃ led to a denser porous structure accompanied by a reduction in WHC. Meanwhile, the extrudate with a CaCO₃/NaHCO₃ ratio of 0:2 exhibited the lowest hardness, measuring 8.87 N. As the proportion of NaHCO₃ increased, the pH shifted toward the alkaline range. This increase in pH enhanced the flexibility of the protein structure, leading to a significant rise in the proportion of disordered structures in the protein secondary structure, such as random coil and β-sheet, which facilitated the formation of an elastic gel network. In conclusion, both CaCO₃ and NaHCO₃ significantly modulated the porous structure of the protein–starch gel network formed during extrusion. This provides a new perspective for investigating the relationship between the protein–starch gel network and the quality characteristics of extruded products. Full article

(This article belongs to the Special Issue Gels for Plant-Based Food Applications (2nd Edition))

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26 pages, 694 KB

Open AccessReview

Hydrogel-Based Therapeutic Strategies for Post-Cholecystectomy NAFLD: Targeting Bile Acid Signaling, Gut Microbiota, Inflammation, and Hepatic Fibrosis

by Georgiana-Andreea Marinescu, Alexandra-Daniela Rotaru-Zavaleanu, Emil-Tiberius Trasca, Elena-Irina Caluianu, Oana Taisescu, Andrei Gresita, Madalina Iuliana Musat, Dumitru Radulescu, Razvan Mercut and Citto-Iulian Taisescu

Gels 2026, 12(2), 179; https://doi.org/10.3390/gels12020179 - 20 Feb 2026

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Abstract

Post-cholecystectomy non-alcoholic fatty liver disease (NAFLD), now encompassed within metabolic dysfunction-associated steatotic liver disease (MASLD), is increasingly linked to persistent disruption of bile acid kinetics and gut–liver axis signaling after gallbladder removal. Continuous bile delivery to the intestine reshapes the bile acid pool, [...] Read more.

Post-cholecystectomy non-alcoholic fatty liver disease (NAFLD), now encompassed within metabolic dysfunction-associated steatotic liver disease (MASLD), is increasingly linked to persistent disruption of bile acid kinetics and gut–liver axis signaling after gallbladder removal. Continuous bile delivery to the intestine reshapes the bile acid pool, perturbs FXR–FGF19/TGR5 pathways, remodels gut microbiota, and compromises epithelial barrier integrity, collectively promoting portal endotoxemia, chronic hepatic inflammation, and fibrogenic remodeling. Hydrogel-based biomaterials offer a mechanistically aligned therapeutic platform for this setting because they enable localized, sustained, and stimuli-responsive interventions at intestinal or hepatic sites. Functional hydrogels can sequester excess bile acids, protect and deliver probiotics/prebiotics/postbiotics, reinforce mucosal barrier function, and provide controlled release of anti-inflammatory or antifibrotic agents with reduced systemic exposure. In this review, we map emerging hydrogel strategies relevant to post-cholecystectomy NAFLD across four pathogenic nodes, bile acid dysregulation, dysbiosis, inflammation, and fibrosis, and highlight design principles (polymer chemistry, charge/hydrophobicity balance, mucoadhesion, and pH/redox/enzyme responsiveness) that enable targeted modulation of the gut–liver axis. Finally, we identify key translational gaps, including the lack of post-cholecystectomy-specific experimental models and standardized outcome measures integrating bile acid profiling, microbiome readouts, and hepatic histology. Hydrogel technologies represent a promising route toward localized and multimodal therapy in metabolic liver disease, warranting focused preclinical validation and clinical development. Full article

(This article belongs to the Special Issue Hydrogels in Biomedicine: Drug Delivery and Tissue Engineering)

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20 pages, 4030 KB

Open AccessArticle

Zwitterionic Polymer Gel Fracturing Fluid with Molecular Interface Regulation for Pretreatment-Free Flowback Recycling

by Qingguo Wang, Cuilong Kong, Zhixuan Zhu, Guang Shi, Xuesong Lin, Shengnan Shi, Silong Gai and Jianxun Meng

Gels 2026, 12(2), 178; https://doi.org/10.3390/gels12020178 - 19 Feb 2026

Viewed by 241

Abstract

High salinity and hardness in flowback fluids from tight reservoirs severely degrade the performance of conventional fracturing fluids, leading to formation damage and imposing major constraints on water recycling. An innovative in situ molecular interface regulation strategy that bypasses the need for costly [...] Read more.

High salinity and hardness in flowback fluids from tight reservoirs severely degrade the performance of conventional fracturing fluids, leading to formation damage and imposing major constraints on water recycling. An innovative in situ molecular interface regulation strategy that bypasses the need for costly pretreatment was proposed. A novel zwitterionic polymer was synthesized by grafting trimethylamine N-oxide (TMAO) onto hydrolyzed polyacrylamide. This hydrolyzed polyacrylamide grafted with trimethylamine N-oxide polymer (HPAMT) leverages zwitterionic TMAO groups to form a robust hydration layer approximately 0.25 nm thick on the polymer chains. Each TMAO group can immobilize up to 22.2 water molecules, effectively shielding the polymer from the detrimental effects of ions like Ca²⁺ and Na⁺, thereby preventing chain curling and preserving cross-linking sites. Experimental results demonstrate that HPAMT fracturing fluid prepared with untreated flowback fluids retains over 70% of its initial viscosity. The HPAMT fracturing fluid exhibits superior thermal and shear stability, maintaining more than 90% viscosity after exposure to 90 °C and the shear rate of 170 s⁻¹ for 60 min. Furthermore, HPAMT provides excellent proppant suspension, exceeding 60 min of static settling time. The broken gel viscosity remains below 5 mPa·s, enabling the direct reuse of flowback water. This technology overcomes the critical compatibility issue between traditional polymers and challenging brine chemistry, significantly reducing freshwater consumption and operational costs, thus presenting a viable and innovative solution for enhancing the environmental sustainability of unconventional resource development. Full article

(This article belongs to the Section Gel Applications)

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24 pages, 8241 KB

Open AccessArticle

Effect of Different Reinforcing Fibers on the Properties of Phenolic Aerogel Composites

by Junjie Xu, Xudong Shao, Lijun Lei, Xin Zhang, Jianlong Chang and Hui Gao

Gels 2026, 12(2), 177; https://doi.org/10.3390/gels12020177 - 19 Feb 2026

Viewed by 290

Abstract

With the rapid development of aerospace technology towards hypersonic vehicles, the synergistic demand for lightweighting and high-efficiency thermal insulation performance of ablation-resistant thermal insulation materials is becoming increasingly urgent. In this study, nanoporous phenolic resin was used as the matrix to prepare quartz [...] Read more.

With the rapid development of aerospace technology towards hypersonic vehicles, the synergistic demand for lightweighting and high-efficiency thermal insulation performance of ablation-resistant thermal insulation materials is becoming increasingly urgent. In this study, nanoporous phenolic resin was used as the matrix to prepare quartz fiber-reinforced phenolic aerogel composites (QF/PF), mullite fiber-reinforced phenolic aerogel composites (MF/PF), and carbon fiber-reinforced phenolic aerogel composites (CF/PF), and the influence mechanisms of different reinforcing fibers on the properties of the composites were systematically investigated. QF/PF exhibits optimal thermal insulation performance with a thermal conductivity of 0.1 W/(m·K) at 20–200 °C, followed by MF/PF with a thermal conductivity of 0.11 W/(m·K). Relatively weak thermal insulation performance is demonstrated in CF/PF, whose thermal conductivity reaches 0.14 W/(m·K). However, in terms of mechanical properties, CF/PF is outstanding, with a tensile strength of 54.62 MPa and a bending strength of 29.69 MPa. In addition, the most excellent ablation resistance is displayed in CF/PF, with a linear ablation rate of 0.13 mm/s and a mass ablation rate of 0.0435 g/s, which are significantly lower than QF/PF and MF/PF. This study provides an important basis for the selection of reinforcing fibers in different application scenarios. QF/PF or MF/PF is preferred for high thermal insulation requirements. CF/PF is favored for high load-bearing requirements or extreme ablative environments. Full article

(This article belongs to the Section Gel Chemistry and Physics)

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15 pages, 1608 KB

Open AccessArticle

Performance Improvement of the Acrylic Acid–Polyvinyl Alcohol Gel Dosimeter with an Organic Additive for Radiation Oncology Applications

by Belal Moftah, Khalid A. Rabaeh, Akram A. Moussa, Abdullah S. Bani Issa and Md A. Al Kafi

Gels 2026, 12(2), 176; https://doi.org/10.3390/gels12020176 - 17 Feb 2026

Viewed by 158

Abstract

This study reports the first preparation and characterization of an acrylic acid–glucose–polyvinyl alcohol (ACAGLPVA) polymer gel dosimeter incorporating glucose as an organic additive for radiation oncology applications. Five formulations with glucose concentrations of 0, 10, 20, 25, and 30 wt% were irradiated using [...] Read more.

This study reports the first preparation and characterization of an acrylic acid–glucose–polyvinyl alcohol (ACAGLPVA) polymer gel dosimeter incorporating glucose as an organic additive for radiation oncology applications. Five formulations with glucose concentrations of 0, 10, 20, 25, and 30 wt% were irradiated using a 6-MV photon beam at doses of 0–60 Gy, and the transverse relaxation rate (R₂) was measured by nuclear magnetic resonance (NMR) relaxometry. The optimal formulation (25 wt% glucose) demonstrated an excellent linear dose response between 0 and 30 Gy (R² = 0.9979) with a sensitivity of 0.177 s⁻¹ Gy⁻¹, followed by a non-linear response at 30–60 Gy. The dosimeter exhibited dose rate independence (200–600 cGy/min), energy independence (6–15 MV), temperature independence (5–35 °C), and post-irradiation stability for at least 7 days. These characteristics demonstrate the potential of ACAGLPVA gel dosimeters for accurate three-dimensional dose verification in modern radiotherapy applications. Full article

(This article belongs to the Special Issue Recent Advances in Gel-Based Materials for Cancer Therapy)

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19 pages, 4417 KB

Open AccessArticle

Effects of Isolated Pea Protein on Extrusion-Induced Gelation and Gel-like Network Formation in Low-Moisture Meat Analog Systems

by Hyun-Woo Choi, Yu Zhang, Yunju Lee, Hyerim Jeon, Gi-Hyung Ryu and Bon-Jae Gu

Gels 2026, 12(2), 175; https://doi.org/10.3390/gels12020175 - 16 Feb 2026

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Abstract

Low-moisture meat analogs (LMMAs) typically exhibit highly expanded structures with large air cells, which differ from the dense and fibrous architecture observed in high-moisture systems. This study investigated the role of isolated pea protein (IPP) in extrusion-induced protein gelation and gel-like network formation [...] Read more.

Low-moisture meat analogs (LMMAs) typically exhibit highly expanded structures with large air cells, which differ from the dense and fibrous architecture observed in high-moisture systems. This study investigated the role of isolated pea protein (IPP) in extrusion-induced protein gelation and gel-like network formation in LMMAs produced by low-moisture extrusion. By partially substituting isolated soy protein (ISP) with IPP, changes in expansion behavior, protein network structure, and gel-related physicochemical properties were systematically evaluated. Increasing IPP content markedly reduced expansion and air-cell size, leading to the formation of a dense and continuous gel-like protein network with enhanced fibrous alignment. At IPP substitution levels of 20–30%, the extrudates exhibited gel structures and fibrous characteristics comparable to those of high-moisture meat analogs. As IPP incorporation increased, water holding capacity, springiness, and cohesiveness declined, while mechanical resistance parameters, including chewiness, cutting strength, and integrity index, progressively increased, indicating gel network densification. Nitrogen solubility index analysis further revealed distinct protein denaturation and gelation behaviors between IPP- and ISP-based systems. These results demonstrate that controlled incorporation of IPP effectively modulates extrusion-induced gelation and gel network architecture in low-moisture meat analogs, providing mechanistic insights into gel-based structuring strategies for plant-based meat systems. Full article

(This article belongs to the Special Issue Oleogels, Bigels, and Emulgels: Fabrication, Application and Research Trends (2nd Edition))

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21 pages, 3989 KB

Open AccessArticle

Ultrasound-Treated Dendrobium officinale Polysaccharides as Functional Ingredients for Plant-Based Yogurt: Enhancing Gel Properties of Soy Protein Isolate

by Yuhan Cao, Jinyao Zha, Yongtuo Zhang, Taoshi Liu, Jianming Cheng, Fan Zhao and Feng Xue

Gels 2026, 12(2), 174; https://doi.org/10.3390/gels12020174 - 16 Feb 2026

Viewed by 155

Abstract

The application of bioactive polysaccharides from medicine–food homology sources in the food industry still poses a significant challenge. This study investigated the effects of ultrasonically modified polysaccharides from Dendrobium officinale on the physicochemical properties of plant-based yogurt. The Dendrobium officinale polysaccharides were treated [...] Read more.

The application of bioactive polysaccharides from medicine–food homology sources in the food industry still poses a significant challenge. This study investigated the effects of ultrasonically modified polysaccharides from Dendrobium officinale on the physicochemical properties of plant-based yogurt. The Dendrobium officinale polysaccharides were treated with ultrasound at varying power levels (200–600 W) and durations (20–40 min). The modified polysaccharides (0.5%) were then incorporated into soy-protein-isolate-based (5%) yogurt, and the resulting composites were characterized in terms of their structural and functional properties. Results showed that optimal treatment (400 W, 20 min) reduced the particle size of the polysaccharides while enhancing their hydrophilicity and hydroxyl group exposure. The incorporation of these modified polysaccharides into SPI gels promoted probiotic growth, lowered the gel pH, and facilitated the formation of protein gel. Consequently, the resulting gels exhibited a denser microstructure, along with superior gel strength, water-holding capacity, apparent viscosity, storage modulus, deformation resistance, and antioxidant activity (scavenging DPPH and ABTS radicals). These findings suggest that ultrasonic treatment not only modifies polysaccharides from Dendrobium officinale to enhance their bioactivity but also augments their capacity to facilitate protein gel formation. This work provides the evidence that ultrasound-modified polysaccharides from Dendrobium officinale can simultaneously act as prebiotic stimulators and structural reinforcements, offering a novel strategy for designing high-quality plant-based yogurts. Full article

(This article belongs to the Special Issue Plant-Based Gels for Food Applications)

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17 pages, 7470 KB

Open AccessArticle

Unravelling the Deterioration Mechanism of the Coated Tofu Gel During Cold Storage: The Role of Protein Oxidation

by Saihua Sun, Xiaohu Zhou, Yang Liu, Xinrui Diao, Jian Zeng, Jie Chen, Fenfang Song, Xiangjun Li, Xiaojie Zhou, Hao Chen, Zhanrui Huang, Liangzhong Zhao, Dajun Yang and Xiangle Huang

Gels 2026, 12(2), 173; https://doi.org/10.3390/gels12020173 - 15 Feb 2026

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Abstract

Coated tofu is prone to spoilage and degradation during processing, storage, and transportation. As the material basis for gel of coated tofu, proteins determine coated tofu’s unique qualities, such as its colour, flavour, and texture. This study aimed to investigate the changes in [...] Read more.

Coated tofu is prone to spoilage and degradation during processing, storage, and transportation. As the material basis for gel of coated tofu, proteins determine coated tofu’s unique qualities, such as its colour, flavour, and texture. This study aimed to investigate the changes in the quality of coated tofu and the physicochemical properties of its proteins during cold storage (4 °C and 10 °C, 14 days), as well as the intrinsic correlations between these variables. Quality deterioration and protein structural changes were significantly slower at 4 °C than at 10 °C, with lower temperature effectively delaying quality loss. The results indicated that as storage time increased, the freshness of coated tofu declined, its textural properties significantly deteriorated, and the protein gel network structure became impaired. Meanwhile, the proteins underwent significant oxidative denaturation, characterized by a decrease in the free thiol group content and an increase in surface hydrophobicity. The tertiary structure exhibited unfolding and disruption, while the secondary structure transitioned from an ordered to a disordered state. Specifically, the contents of α-helixes and β-sheets decreased significantly, reaching 34.96% and 8.68%, respectively, after 14 days of storage at 4 °C. In contrast, the contents of β-turns and random coils increased to 30.11% and 26.25%, respectively, under the same storage conditions. The subunit bands of the 11S and 7S proteins gradually weakened, and the protein structure tended to loosen. Correlation analysis revealed that the oxidative denaturation, structural depolymerization, and reaggregation of proteins were highly significantly correlated with the textural breakdown and colour deterioration of coated tofu, which together contributed to the quality degradation of coated tofu during cold storage. The findings of this study provide fundamental data and technical support for the development of cold storage methods for coated tofu. Full article

(This article belongs to the Special Issue Gels for Plant-Based Food Applications (2nd Edition))

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19 pages, 5047 KB

Open AccessArticle

Rheology and Molecular Mechanisms of Fracturing Fluids: A Comparison of Three Thickener Types—A Case Study

by Ke Xu, Jing Long, Xu Liang, Dingwei Weng, Pinhong Zhu, Yonghang Yi, Yingxing Chen and Cunchuan Zheng

Gels 2026, 12(2), 172; https://doi.org/10.3390/gels12020172 - 14 Feb 2026

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Abstract

To address the lack of systematic comparison regarding rheological properties and the unclear structure–property relationships among three core fracturing fluid materials including synthetic polymers, vegetable gums, and microbial polysaccharides, this study selected acrylamide-based polymers, hydroxypropyl guar gum and xanthan gum as the representative [...] Read more.

To address the lack of systematic comparison regarding rheological properties and the unclear structure–property relationships among three core fracturing fluid materials including synthetic polymers, vegetable gums, and microbial polysaccharides, this study selected acrylamide-based polymers, hydroxypropyl guar gum and xanthan gum as the representative systems. The steady-state viscosity, rheological curves, thixotropy, viscoelasticity, and temperature-shear resistance of the three samples were systematically characterized at concentrations ranging from 0.1 to 0.7 wt% using an MCR301 rotational rheometer. The outcomes indicate that the structural strength values of all three materials increase with rising concentration, but their rheological behaviors and stability differ significantly due to distinct molecular structures. The acrylamide-based copolymer forms a temporary network via weak hydrogen bonds (amide-carboxyl or amide-amide) and physical entanglements, exhibiting thixotropy and a stress pre-elastic response. The most significant effects occur at 0.7 wt%, with a thixotropic loop area of 2.874 Pa·s⁻¹ and a stress overshoot of 4.97 Pa.; hydroxypropyl guar gum has insufficient thermal stability and poor heat resistance. Its viscosity retention rate is as low as 31%, and it always exhibits a solution-type rheological property of G′ < G″; the xanthan gum exhibits elastic gel properties with tanδ < 1 due to its double-helix molecular structure. It has excellent temperature shear tolerance and the viscosity retention value can reach up to 98.6 mPa·s. Two mathematical models were established and demonstrated strong applicability: a modified Carreau model for flow curve fitting yielded a coefficient of determination (R²) greater than 0.95, enabling accurate description of fluid-type transitions; a four-parameter equation for temperature–shear resistance curves also achieved an R² above 0.95, effectively characterizing viscosity evolution with temperature. Full article

(This article belongs to the Section Gel Analysis and Characterization)

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24 pages, 2152 KB

Open AccessArticle

Characterization of Hydrogel Deformation Using Two-Parameter Hyperelastic Models

by Joseph M. Scalet, Faiz Mandani and Stevin H. Gehrke

Gels 2026, 12(2), 171; https://doi.org/10.3390/gels12020171 - 14 Feb 2026

Viewed by 233

Abstract

Hyperelastic models for the deformation of hydrogels were evaluated as alternatives to the widely used neo-Hookean model. Poly(ethylene glycol diacrylate) (PEGDA) was synthesized via photopolymerization, with precursor molecular weights from 700 to 4000 Da and synthesis concentrations between 5 and 30 wt% in [...] Read more.

Hyperelastic models for the deformation of hydrogels were evaluated as alternatives to the widely used neo-Hookean model. Poly(ethylene glycol diacrylate) (PEGDA) was synthesized via photopolymerization, with precursor molecular weights from 700 to 4000 Da and synthesis concentrations between 5 and 30 wt% in water. Hydrogels are often modeled as neo-Hookean solids; this model holds only over a limited strain range. To model deformation over a broader range and seek additional insight into gel network structures, the Mooney–Rivlin, Ogden, Rubinstein–Panyukov, and Localization models were applied to uniaxial compression data and their fits assessed against “Mooney plots” of reduced stress versus the inverse extension ratio. The Ogden model best fits the stress–strain curves to higher ratios and the reduced stress plots over the broadest range of formulations. The Localization and Rubinstein–Panyukov models fit well above c*, the overlap concentration, capturing low-strain behavior and the observed maxima under compression in Mooney plots. The Mooney–Rivlin model fit the stress–strain curves but was unable to fit the reduced stress plots. The Localization and Rubinstein–Panyukov model parameters suggest that entanglements play a significant role at all concentrations, with their contribution decreasing as the network concentration increases. This demonstrates the potential of using two-parameter models to understand the deformation of hydrogels. Full article

(This article belongs to the Section Gel Chemistry and Physics)

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38 pages, 8837 KB

Open AccessReview

Emerging Platforms for High-Efficiency Solar-Driven Interfacial Evaporation Desalination: MXene-Based Hydrogels/Aerogels

by Yue Gao, Yucheng Yang, Dongdi Yang, Fei Sun and Xiaoxiao Wang

Gels 2026, 12(2), 170; https://doi.org/10.3390/gels12020170 - 14 Feb 2026

Viewed by 327

Abstract

The sustainable supply of freshwater resources is facing serious challenges due to the rapid industrial development, massive expansion of urbanization, and increasing environmental pollution. Solar-driven interfacial evaporation desalination (SIED) is considered one of the most promising candidates to tackle water scarcity and energy [...] Read more.

The sustainable supply of freshwater resources is facing serious challenges due to the rapid industrial development, massive expansion of urbanization, and increasing environmental pollution. Solar-driven interfacial evaporation desalination (SIED) is considered one of the most promising candidates to tackle water scarcity and energy crisis, owing to its sustainable solar energy, abundant water sources, and pollution-free characteristic. MXene has attracted considerable attention in the domain of purified water production, owing to its remarkable properties, including tunable hydrophilicity, ease of processing, resistance to fouling, mechanical strength, and photothermal conversion capabilities. This review provides a comprehensive overview of the research progress of hydrogels/aerogels in the SIED field. Firstly, the synthesis strategy and the significantly distinctive features of MXene and its nanocomposites are outlined. Secondly, based on the photothermal conversion capacity and ease of modulation of MXene, various fabrication processes of MXene aerogels are analyzed, and the varying wettability levels of the MXene aerogel-based evaporators are discussed and summarized. Thirdly, the properties of MXene hydrogel-based evaporators are discussed from four perspectives: photothermal conversion capacity, water transport capacity, evaporation enthalpy regulation, and salt resistance. Finally, the challenges and issues related to the development of MXene hydrogels/aerogels in SIED are further discussed. Full article

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28 pages, 4178 KB

Open AccessReview

Natural pH-Sensitive Intelligent Edible Gel-Based Packaging: From Structural Design to Fruit Freshness Monitoring

by Tong Zhao, Lulu Wang, Xinyue Wang, Meng Zhang, Xin Zhang, Chen Li, Qian Zhang, Yan Zhao and Lixia Wang

Gels 2026, 12(2), 169; https://doi.org/10.3390/gels12020169 - 14 Feb 2026

Viewed by 302

Abstract

The escalating demand for global fruit logistics underscores the urgency of packaging innovations to reconcile preservation efficiency with environmental sustainability, particularly addressing microplastic pollution from conventional plastics and safety hazards posed by synthetic pH-sensitive pigments. Natural pH-sensitive intelligent edible gel-based packaging, which integrates [...] Read more.

The escalating demand for global fruit logistics underscores the urgency of packaging innovations to reconcile preservation efficiency with environmental sustainability, particularly addressing microplastic pollution from conventional plastics and safety hazards posed by synthetic pH-sensitive pigments. Natural pH-sensitive intelligent edible gel-based packaging, which integrates non-toxic indicators into biopolymer gel matrices, offers a viable solution by visually tracking freshness through colorimetric responses to pH fluctuations during storage and transportation. This review systematically synthesizes recent progress in material design, including the development of edible films and coatings, and evaluates the functional mechanisms of natural pH indicators within these systems. Applications across diverse fruit categories demonstrate their efficacy in delaying ripening, inhibiting microbial growth, and signaling quality degradation via dynamic color shifts. Despite enabling real-time, visual freshness monitoring, challenges in mechanical robustness, water resistance, and scalable manufacturing remain. Future advancements should prioritize the integration of multifunctional systems, such as gas conditioning technologies and bioactive components, to enhance practical performance and align with sustainable food preservation objectives, ultimately reducing food waste and elevating consumer safety standards. Full article

(This article belongs to the Special Issue Composite Gel Systems: Materials, Formation Behaviors and Functional Food Packaging Applications)

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19 pages, 1282 KB

Open AccessReview

Research on Polysaccharide–Protein Composite Hydrogels for Gastrointestinal Targeted Delivery: A Review

by Jingjing Guo, Yuxin Cai, Ran Zou, Chen Ai and Qun Fu

Gels 2026, 12(2), 168; https://doi.org/10.3390/gels12020168 - 14 Feb 2026

Viewed by 324

Abstract

Polysaccharide–protein composite hydrogels have demonstrated remarkable potential in targeted gastrointestinal delivery owing to their excellent biocompatibility, adjustable physicochemical characteristics, and intelligent responsiveness. This review provides a comprehensive overview of the underlying mechanisms and diverse applications of these composite hydrogels in gastrointestinal targeted delivery, [...] Read more.

Polysaccharide–protein composite hydrogels have demonstrated remarkable potential in targeted gastrointestinal delivery owing to their excellent biocompatibility, adjustable physicochemical characteristics, and intelligent responsiveness. This review provides a comprehensive overview of the underlying mechanisms and diverse applications of these composite hydrogels in gastrointestinal targeted delivery, with a particular emphasis on their stimuli-responsive release behaviors triggered by internal and external factors such as pH, enzymes, magnetic fields. Special attention is also given to their advantages in protecting sensitive bioactive ingredients, including curcumin, EGCG, probiotics. Furthermore, this review highlights their capabilities in achieving high encapsulation efficiency, smart controlled release and targeted delivery, while also presenting current challenges associated with material stability, targeting precision, large-scale production, and clinical translation. Finally, future perspectives are discussed, focusing on the development of multi-response system design, innovative biomaterials, advanced manufacturing technology applications, and AI-assisted optimization. These directions aim to provide theoretical foundations and technical strategies for advanced research and practical applications of polysaccharide–protein composite hydrogels in a targeted gastrointestinal delivery system. Overall, this review underscores the significant promise of polysaccharide–protein composite hydrogels as intelligent gastrointestinal delivery platforms and provides a systematic reference for their rational design and future translational development. Full article

(This article belongs to the Special Issue Recent Developments in Food Gels (3rd Edition))

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16 pages, 7120 KB

Open AccessArticle

Electron Beam-Irradiated g-C₃N₄/Ti₃C₂ Nanocomposite Embedded in PVA/SA Hydrogel: An Integrated Platform with Enhanced Photocatalytic Antibacterial Activity

by Rui Feng, Xuguang Chen, Yue Wu, Kaidi Xu, Yu Zhao, Jiale Lu, Zenghui Shi, Huangqin Chen and Bin Huang

Gels 2026, 12(2), 167; https://doi.org/10.3390/gels12020167 - 14 Feb 2026

Viewed by 212

Abstract

Photodynamic antibacterial therapy presents a promising strategy for combating bacterial infections due to its non-invasive nature and low potential for inducing resistance. In this work, we developed a series of electron beam-modified graphitic carbon nitride (g-C₃N₄, CN) and titanium [...] Read more.

Photodynamic antibacterial therapy presents a promising strategy for combating bacterial infections due to its non-invasive nature and low potential for inducing resistance. In this work, we developed a series of electron beam-modified graphitic carbon nitride (g-C₃N₄, CN) and titanium carbide (Ti₃C₂, TC) nanocomposites, which were subsequently incorporated into polyvinyl alcohol/sodium alginate (PVA/SA) hydrogels through physical cross-linking. The optimized 200CN/1TC composite hydrogel (where 200CN denotes 200 kGy irradiation dose, and 1TC represents 1 wt% TC content) maintained excellent biocompatibility with cell viability exceeding 80% even at the highest nanomaterial loading (8% 200CN/1TC). Notably, the 8% 200CN/1TC composite hydrogel displayed substantial antibacterial activity, forming inhibition zones of 12.3 mm and 10.8 mm against Staphylococcus aureus and Escherichia coli, respectively. The improved performance may be explained by the combined effects of enhanced electron transfer between the component materials and the unique two-dimensional structure of the nanocomposites, though further investigation is required to fully elucidate the underlying mechanisms. This study provides a feasible approach for developing efficient antibacterial hydrogel systems and offers valuable perspectives on the design of nanomaterial-based biomedical materials for wound healing and infection control applications. Full article

(This article belongs to the Special Issue Design, Fabrication, and Applications of Food Composite Gels)

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21 pages, 8850 KB

Open AccessArticle

Effect of Pre-Hydrolyzed Rice Extrudates with Different Dextrose Equivalent Values on Stability of Emulsion-Type Food for Special Medical Purposes

by Zilong Ge, Chong Liu, Ping Li, Jiarui Zeng, Xiaojun Tang, Pengfei Zhou, Zhihao Zhao, Yuanyuan Deng and Guang Liu

Gels 2026, 12(2), 166; https://doi.org/10.3390/gels12020166 - 14 Feb 2026

Viewed by 235

Abstract

Maltodextrin is the most commonly used carbohydrate ingredient in Food for Special Medical Purposes (FSMP). However, growing evidence suggests that it may trigger intestinal inflammatory responses. Replacing maltodextrin with pre-hydrolyzed rice extrudates represents a viable approach to eliminate such adverse effects. Accordingly, this [...] Read more.

Maltodextrin is the most commonly used carbohydrate ingredient in Food for Special Medical Purposes (FSMP). However, growing evidence suggests that it may trigger intestinal inflammatory responses. Replacing maltodextrin with pre-hydrolyzed rice extrudates represents a viable approach to eliminate such adverse effects. Accordingly, this study prepared pre-hydrolyzed rice extrudates with different dextrose equivalent (DE) values and investigated their impact on the physicochemical properties of emulsion-type FMSP containing carbohydrates, casein, and soybean oil with increasing addition levels. The emulsion particle size of pre-hydrolyzed rice extrudates with different DE values showed a gradual upward trend, while the zeta potential gradually decreased. As the DE value increased, its influence on the zeta potential and viscosity of the emulsion diminished. However, samples with lower DE values contributed positively to reducing the centrifugal sedimentation rate of the emulsion, which was mainly attributed to their higher viscosity. In contrast, the turbidity and adsorption rate of emulsion samples with higher DE values were less affected by the addition level. Through turbiscan stability index and multi-index comprehensive evaluation, the optimal addition levels for pre-hydrolyzed rice extrudates with different DE values were obtained. The findings provide important insights for promoting the application of pre-hydrolyzed rice extrudates as a substitute for maltodextrin in FMSP. Full article

(This article belongs to the Special Issue Preparation, Structure–Property Relationships, and Applications of Emulsion Gels)

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20 pages, 3410 KB

Open AccessArticle

A Natural Antioxidant-Rich Hydrogel Formulation with Laurus nobilis Hydrosol: Physicochemical and Cosmeceutical Evaluation

by Lea Juretić, Radwan Joukhadar, Emerik Galić, Renata Jurišić Grubešić and Mario Jug

Gels 2026, 12(2), 165; https://doi.org/10.3390/gels12020165 - 14 Feb 2026

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Abstract

Laurus nobilis hydrosol (HyLN), a water-soluble byproduct of essential oil extraction, containing beneficial antioxidants and antimicrobial compounds, was used as a sustainable ingredient in the development of a natural antioxidant-rich hydrogel formulation. Hydrogels were formulated using sodium hyaluronate and xanthan gum, natural ingredients [...] Read more.

Laurus nobilis hydrosol (HyLN), a water-soluble byproduct of essential oil extraction, containing beneficial antioxidants and antimicrobial compounds, was used as a sustainable ingredient in the development of a natural antioxidant-rich hydrogel formulation. Hydrogels were formulated using sodium hyaluronate and xanthan gum, natural ingredients with beneficial effects on the skin, while β-cyclodextrin (βCD) was added to enhance the stability of antioxidants in HyLN. Extensive rheological and textural analyses were employed to optimize the hydrogel formulation for dermal administration, while stability studies assessed the chemical and physical stability of developed formulations. A combination of sodium hyaluronate and xanthan gum provided several HyLN hydrogel formulations with tunable rheological and textural properties, presenting adequate physical and microbiological stability over 6 months of storage. The use of βCD failed to stabilize inherently unstable antioxidants in HyLN hydrogels, yet their residual antioxidant activity remained notable. An in vitro scratch test using a human keratinocyte cell line showed that the developed HyLN gel does not interfere with wound healing. HyLN hydrogels showed a pronounced occlusive effect in vitro, reaching up to 80% of that measured for Vaseline, which helps maintain skin hydration and appearance. Full article

(This article belongs to the Special Issue Polymer-Based Hydrogels Applied in Drug Delivery)

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25 pages, 4355 KB

Open AccessArticle

Preparation and Applicability Evaluation of High-Temperature-Resistant, Breakable Resin–Gel Plugging Agent

by Tao Wang, Jinzhi Zhu, Yingrui Bai, Yanming Yin, Qisheng Jiang, Zhangkun Ren and Jingbin Yang

Gels 2026, 12(2), 164; https://doi.org/10.3390/gels12020164 - 13 Feb 2026

Viewed by 178

Abstract

This study addresses the challenge of high-temperature gas channeling in injection–production wells of karst-fractured reservoirs by developing a high-temperature-resistant resin–gel plugging system capable of withstanding up to 150 °C. The system employs an AMPS/NVP copolymer (molar ratio 3:1) as the polymer matrix, reinforced [...] Read more.

This study addresses the challenge of high-temperature gas channeling in injection–production wells of karst-fractured reservoirs by developing a high-temperature-resistant resin–gel plugging system capable of withstanding up to 150 °C. The system employs an AMPS/NVP copolymer (molar ratio 3:1) as the polymer matrix, reinforced with phenolic resin to enhance the crosslinked network. Additionally, a polyamide microcapsule was utilized to encapsulate the gel breaker, enabling controlled release. The optimized formulation consists of 0.5% NEP, 0.5% DEP, 0.6% HMTA, 0.3% catechol, and 25% resin curing agent. Experimental results demonstrate that the system exhibits excellent stability at 150 °C, with a G′ ≥ 125 Pa and compressive strength > 18 MPa. It also displays strong contamination resistance, showing a viscosity reduction of <9.7% and a storage modulus retention rate > 87% after mixing with drilling fluid. Furthermore, the gel-breaking performance is controllable, achieving a gel-breaking rate ≥ 99.7% within 21 days. Under high-temperature and high-pressure conditions (150 °C), the system demonstrates a plugging efficiency > 92% for simulated fractures with widths ranging from 0.1 to 2 mm. This technology effectively suppresses gas channeling in complex high-temperature formations, making it suitable for gas injection wells in karst-fractured reservoirs. It also holds promise for extension to shale gas wells and geothermal reservoir sealing applications. Full article

(This article belongs to the Topic Polymer Gels for Oil Drilling and Enhanced Recovery)

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14 pages, 4055 KB

Open AccessArticle

Rheological Flow Behavior of Six Gelling Agents and Their Relevance for In Vitro Culture Performance of Medicinal Plants

by Doina Clapa, Monica Hârţa, Bernadette-Emőke Teleky, Ana-Maria Radomir, Adrian George Peticilă and Dorin Ioan Sumedrea

Gels 2026, 12(2), 163; https://doi.org/10.3390/gels12020163 - 12 Feb 2026

Viewed by 201

Abstract

Gelling agents are widely used to solidify plant tissue culture media, yet differences among commercial products may influence the medium’s physical properties and in vitro development of explants. The aim of this study was to characterize the rheological behavior of six gelling agents [...] Read more.

Gelling agents are widely used to solidify plant tissue culture media, yet differences among commercial products may influence the medium’s physical properties and in vitro development of explants. The aim of this study was to characterize the rheological behavior of six gelling agents (Daishin agar, Gelcarin, Gelrite, Microagar, Phytoagar, and Plant agar) and to examine it in parallel with in vitro performance in Hypericum perforatum, Mentha × piperita, and Stevia rebaudiana. Rheological measurements were performed under steady shear by recording apparent viscosity and shear stress across 5–300 s⁻¹. Daishin agar showed the highest apparent viscosity (49,028.95 ± 128 mPa·s), whereas Gelrite exhibited the lowest viscosity (7826.75 ± 98 mPa·s). Plant responses were evaluated after four weeks on PGR-free Driver and Kuniyuki Walnut (DKW) medium by assessing shoot growth, rooting parameters, and shoot water content. In H. perforatum, the longest shoots were obtained on Gelrite (3.92 ± 0.34 cm), accompanied by the highest rooting percentage (95%). In M. × piperita, Gelcarin produced the longest shoots (8.20 ± 0.55 cm) and the highest number of roots per explant (9.75). In S. rebaudiana, Gelcarin promoted superior root elongation (2.86 ± 0.16 cm) and enhanced shoot growth, while Plant agar also supported favorable shoot development. Shoot water content ranged between 74% and 90%, depending on species and gelling agent. These findings highlight the practical relevance of considering low-shear rheological properties when comparing gelling agents for improving the consistency of in vitro culture media. Full article

(This article belongs to the Special Issue Women’s Special Issue Series: Gels (2nd Edition))

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22 pages, 6292 KB

Open AccessArticle

Adhesive Tape Strips and PVA–Borax Hydrogels as Alternative Cleaning Methods to Remove Fungal Proliferation on Canvas Support of Paintings

by Haizea Oliveira-Urquiri, Anxo Méndez, Pilar Bosch-Roig and Patricia Sanmartín

Gels 2026, 12(2), 162; https://doi.org/10.3390/gels12020162 - 12 Feb 2026

Viewed by 297

Abstract

Two commercial adhesive tape strips (Fungi-Tape^TM and Filmoplast^® P) and a polyvinyl alcohol–borax (PVA-B) gel were tested as novel physical cleaning alternatives to micro-aspiration for removing visible fungal colonisation from a cotton canvas. In addition, clove essential oil (CEO) and Cyrene™ [...] Read more.

Two commercial adhesive tape strips (Fungi-Tape^TM and Filmoplast^® P) and a polyvinyl alcohol–borax (PVA-B) gel were tested as novel physical cleaning alternatives to micro-aspiration for removing visible fungal colonisation from a cotton canvas. In addition, clove essential oil (CEO) and Cyrene™ were incorporated in the PVA-B gel for testing the potential of each to improve fungal cleaning. For the trials, canvas mock-ups were separately inoculated with two fungal species identified as Penicillium chrysogenum and Aspergillus westerdijkiae. Removal of fungi and related impacts were evaluated by DOM, FESEM, ATR-FTIR and ImageJ software. Inhibition of fungal spores and residual growth were assessed by in vitro growth tests and CLSM. Removal of A. westerdijkiae was more effective than removal of P. chrysogenum, especially for dense coverage. Both tape strips removed slightly more fungus than micro-aspiration, except for dense coverage of P. chrysogenum. The PVA-B gel, both with and without CEO or Cyrene™, yielded the best (similar) results, removing the fungal material found on the surface and subsurface of canvas without damaging the canvas fibres. Although further testing is required, the antifungal activity of PVA-B gel+ Cyrene™ seems comparable to that of PVA-B gel+ CEO, the former being especially effective against A. westerdijkiae. Full article

(This article belongs to the Special Issue Preparation and Application of New Gel Adsorption Materials)

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31 pages, 5434 KB

Open AccessArticle

Optimization of Wind Turbine Spindle Bearing Gel-like Grease Performance at Extreme Temperatures

by Zhenzhong Tian, Yihao Zhang, Han Peng, Budi Peng and Zihao Meng

Gels 2026, 12(2), 161; https://doi.org/10.3390/gels12020161 - 12 Feb 2026

Viewed by 183

Abstract

With the advancement of wind power technology towards larger-capacity and higher-power turbines, their main shaft bearings face significant lubrication challenges under extreme temperatures. In this study, seven modified greases were prepared by adding 0.5 wt.% of tungsten disulfide (WS₂), zinc sulfide [...] Read more.

With the advancement of wind power technology towards larger-capacity and higher-power turbines, their main shaft bearings face significant lubrication challenges under extreme temperatures. In this study, seven modified greases were prepared by adding 0.5 wt.% of tungsten disulfide (WS₂), zinc sulfide (ZnS), and sulfurized isobutylene (T321). The concentration of all additives is given in weight percent (wt.%). Using a combined approach of friction and wear testing along with rheological analysis, this study systematically evaluated the tribological performance of the greases at high temperature (80 °C)—with the friction coefficient and wear scar diameter as key parameters—and their rheological properties across a wide temperature range (−20 °C to 80 °C), focusing primarily on shear stress and viscosity. All critical input parameters, including temperature, load, and shear rate, were precisely controlled and monitored using calibrated instruments. Results indicate that the WS₂ and T321 compounding system demonstrated optimal performance, achieving a low average coefficient of friction of 0.024 and an average wear scar diameter of only 0.367 mm. At the same time, the WS₂/T321 composite formulation exhibits excellent shear stability at high temperatures and good flow properties at low temperatures, demonstrating optimal viscosity–temperature characteristics. This study develops a promising grease formulation through multidimensional performance evaluation, offering key experimental support for designing high-performance wind turbine spindle bearing greases under high-temperature conditions. Full article

(This article belongs to the Section Gel Chemistry and Physics)

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32 pages, 49351 KB

Open AccessArticle

The Early Age Hydration Products and Mechanical Properties of Autoclaved Cement Paste Incorporating Supplementary Cementitious Materials

by Baoliang Li, Sahi Wail, Liying Shi, Arifuggaman Arif, Binbin Huo and Yongzhen Cheng

Gels 2026, 12(2), 160; https://doi.org/10.3390/gels12020160 - 12 Feb 2026

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Abstract

This study systematically investigated the effects of four supplementary cementitious materials (SCMs), namely ferronickel slag (FNS), lithium slag (LS), steel slag (SS), and ground granulated blast furnace slag (GBFS), on various properties of autoclaved cementitious materials. Cement pastes and mortars with 0% and [...] Read more.

This study systematically investigated the effects of four supplementary cementitious materials (SCMs), namely ferronickel slag (FNS), lithium slag (LS), steel slag (SS), and ground granulated blast furnace slag (GBFS), on various properties of autoclaved cementitious materials. Cement pastes and mortars with 0% and 30% replacement levels were prepared to examine their impacts on early age hydration products and mechanical properties, with comparisons made to specimens under standard 28-day curing. Key findings reveal that autoclaving promoted the formation of tobermorite, crystalline calcium aluminosilicate hydrate (CASH), gypsum and hydrogarnet, with the latter two phases potentially compromising concrete durability. Autoclave curing significantly enhanced SCM reactivity, as evidenced by thermogravimetric analysis: the mass loss below 200 °C (mainly from C–S–H gels decomposition) in SCM-incorporated pastes ranged from 87.0% (SS) to 104.6% (GBFS) of the control value, while the portlandite (Ca(OH)₂) content decreased to between 47.7% (LS) and 82.4% (GBFS) of the control. Among the SCMs studied, autoclaving exhibited the most pronounced activation effect on LS, which also showed superior potential as a GBFS alternative in autoclaved concrete products. However, the low CaO content and acidic nature of LS limited its use to low replacement levels unless supplementary sources of alkalinity and CaO were provided. Full article

(This article belongs to the Special Issue Development and Applications of Advanced Geopolymer Gel Materials)

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13 pages, 6241 KB

Open AccessArticle

Effect of a Localized Oxygen-Releasing Hydrogel Sheet on Early-Stage Infarct Evolution in a Rat Photothrombotic Stroke Model: A Preliminary Study

by Kunhee Han, Hyeong-Joong Yi, Hyoung-Joon Chun, Min Kyun Na, Simon Song, Kyung Min Park and Kyu-Sun Choi

Gels 2026, 12(2), 159; https://doi.org/10.3390/gels12020159 - 12 Feb 2026

Viewed by 192

Abstract

Ischemic stroke triggers hypoxia, inflammation, and oxidative stress. Local oxygen delivery may prevent secondary injuries. Herein, we implanted a catalase-incorporated thiolated gelatin-based oxygen-releasing hydrogel sheet in a rat model of photothrombosis to evaluate early infarct attenuation and feasibility. Male Sprague–Dawley rats were allocated [...] Read more.

Ischemic stroke triggers hypoxia, inflammation, and oxidative stress. Local oxygen delivery may prevent secondary injuries. Herein, we implanted a catalase-incorporated thiolated gelatin-based oxygen-releasing hydrogel sheet in a rat model of photothrombosis to evaluate early infarct attenuation and feasibility. Male Sprague–Dawley rats were allocated to four groups (n = 6/group): control at 24 h (G1), with hydrogel sheet at 24 h (G2), control at 72 h (G3), and with hydrogel sheet at 72 h (G4). Focal ischemia was induced with Rose Bengal and targeted illumination through a 6.0-mm cranial defect. A hydrogel sheet was applied to the cortex after surgery. The infarct burden was assessed by 2,3,5-triphenyltetrazolium chloride (TTC) staining and magnetic resonance imaging (MRI), while mRNA expression levels of tumor necrosis factor-α (TNF-α), brain-derived neurotrophic factor (BDNF), and superoxide dismutase (SOD) were measured by quantitative reverse transcription PCR. Body weight was monitored as a safety measure. At 24 h, TTC showed a significant infarct reduction in G2 compared with G1. At 72 h, infarct measures did not differ significantly between G4 and G3. MRI and gene expression analyses did not show statistically significant between-group differences and are presented as exploratory outcomes. Weight and perioperative status were similar across groups, indicating short-term tolerability. The hydrogel sheet was associated with reduced TTC-defined infarct burden at 24 h in this model; confirmatory studies will require larger, powered cohorts, longer follow-up with functional testing, and in vivo oxygen release profiling to optimize dose, placement, and exposure time. Full article

(This article belongs to the Section Gel Processing and Engineering)

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18 pages, 4031 KB

Open AccessArticle

A Keratin-Waste Derived Multifunctional Gel System: Reusable Activated Carbon/Alginate Microbeads for Simultaneous Dye and Pharmaceutical Adsorption

by Yue Wang, Lei Zhao, Zhiying Li, Qingqing Xue, Zhenhao Tang, Ge Zhang, Zhiqiang Li and Zifan Wang

Gels 2026, 12(2), 158; https://doi.org/10.3390/gels12020158 - 11 Feb 2026

Viewed by 256

Abstract

The resource utilization of keratin waste has garnered significant attention, yet the processing of yak hair keratin in underdeveloped regions such as Tibet and Qinghai in China remains challenging. This study addresses these concerns by carbonizing yak hair keratin waste using a steam [...] Read more.

The resource utilization of keratin waste has garnered significant attention, yet the processing of yak hair keratin in underdeveloped regions such as Tibet and Qinghai in China remains challenging. This study addresses these concerns by carbonizing yak hair keratin waste using a steam flash explosion (SFE) technique for 150 s, which is followed by activation with KOH at various ratios and subsequent to produce activated carbon (AC) samples. The AC was then combined with sodium alginate (Alg) at different ratios, pH and applied voltage to yield AC−Alg gel microbeads using an electrospinning method. The characterization of the AC and AC–Alg gel microbeads was conducted using SEM, BET, TG, and FT-IR analysis. In adsorption studies, AC−Alg_0.5U gel microbeads prepared with optimized conditions (pH 7, 11 kV, 19 G needle) were used to remove dyes (methylene blue (MB) and methyl orange (MO)) and antibiotic minocycline hydrochloride (MH). Various parameters such as temperature, pH, and adsorbent dose were optimized to obtain the maximum adsorption performance under model concentrations. The experimental results showed that the AC−Alg_0.5U gel microbeads can effectively adsorb MB and MO with adsorption capacities of 1038.9 mg/g and 206.2 mg/g, respectively. Moreover, the microbeads had the best adsorption performance for MH (1694.2 mg/g), with the kinetics most accurately represented by the pseudo-second-order kinetic model (R² = 0.999), and the isotherm followed the Langmuir model (R² = 0.984). The microbeads maintained a high adsorption capacity of 75% after six cycles. The composite gel microbeads not only utilize yak hair keratin waste but also will be used as durable and favorable adsorbents for the removal of pollutants. Full article

(This article belongs to the Special Issue Design of Hydrogels and Hydrogel-Derived Materials: Focus on Wastewater, Agriculture, and Biomedicine)

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19 pages, 3815 KB

Open AccessArticle

CNF/p(AM-co-KAA) Semi-Interpenetrating Network Hydrogel Fertilizer Carriers for Enhanced Nutrient Use Efficiency, Water Retention, and Salt–Alkali Resistance

by Jingxuan Pan, Yanhong Wang, Jingwei Wang, Weiwen Qiu, Qiang Xiao and Shuqi Dong

Gels 2026, 12(2), 157; https://doi.org/10.3390/gels12020157 - 11 Feb 2026

Viewed by 188

Abstract

Developing functional agricultural materials that synchronize nutrient release, water retention, and soil amendment is crucial to advancing resource-efficient, sustainable farming systems. However, integrating these multifunctional properties within a single material remains a significant challenge. In this work, we fabricated a multifunctional hydrogel (CPAUH) [...] Read more.

Developing functional agricultural materials that synchronize nutrient release, water retention, and soil amendment is crucial to advancing resource-efficient, sustainable farming systems. However, integrating these multifunctional properties within a single material remains a significant challenge. In this work, we fabricated a multifunctional hydrogel (CPAUH) via a one-pot synthesis strategy, which was composed of carboxylated cellulose nanofibers as a rigid network combined with poly(AA-co-KAA), forming a semi-interpenetrating network (semi-IPN) for loading urea and humic acid. The structure and properties of hydrogels were characterized by FTIR, TGA, SEM, and XPS. The CPAUH exhibited outstanding mechanical strength (0.169 MPa), water absorption capacity (121.65 g g⁻¹), and retained 118 g g⁻¹ after three absorption–desorption cycles, demonstrating remarkable structural stability. Nutrient release kinetics revealed sustained-release behavior, with cumulative elution of only 66.91% for urea and 92.45% for humic acid over 15 days. Under salt stress, the 1.5% CPAUH amendment (P2) markedly enhanced wheat growth compared with the non-amended control (P0), as reflected by significant increases in plant height, chlorophyll content, fresh weight, dry weight, and nitrogen uptake. Concurrently, CPAUH application effectively improved soil conditions by reducing electrical conductivity by 39.16% (to 4.38 mS·cm⁻¹). These collective findings of CPAUH hydrogel offer substantial potential as a multifunctional soil amendment for enhancing water-fertilizer efficiency, reclaiming saline–alkali soils, and improving crop productivity under resource-limited conditions. Full article

(This article belongs to the Special Issue Design of Hydrogels and Hydrogel-Derived Materials: Focus on Wastewater, Agriculture, and Biomedicine)

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Gels, Volume 12, Issue 2 (February 2026) – 89 articles

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