Gels | October 2025 - Browse Articles

24 pages, 2544 KB

Open AccessArticle

Formulation and Optimization of a Melissa officinalis-Loaded Nanoemulgel for Anti-Inflammatory Therapy Using Design of Experiments (DoE)

by Yetukuri Koushik, Nadendla Rama Rao, Uriti Venkatesh Sri, Gottam Venkata Rami Reddy, Amareswarapu V. Surendra and Thalla Sreenu

Gels 2025, 11(10), 776; https://doi.org/10.3390/gels11100776 (registering DOI) - 26 Sep 2025

Abstract

This study reports the development and optimization of a Melissa officinalis oil-based nanoemulgel for transdermal delivery using a Design-of-Experiments (DoE) approach. A Central Composite Design (CCD) was applied to optimize Tween 80 concentration and homogenization time, resulting in a nanoemulsion with a droplet [...] Read more.

This study reports the development and optimization of a Melissa officinalis oil-based nanoemulgel for transdermal delivery using a Design-of-Experiments (DoE) approach. A Central Composite Design (CCD) was applied to optimize Tween 80 concentration and homogenization time, resulting in a nanoemulsion with a droplet size of 127.31 nm, PDI of 17.7%, and zeta potential of −25.0 mV, indicating good colloidal stability. FTIR analysis confirmed the presence of functional groups such as O–H, C=O, and C–O–C, supporting the oil’s phytochemical richness and therapeutic potential. DSC analysis revealed enhanced thermal stability and successful encapsulation, while SEM imaging showed a uniform and spherical microstructure. The drug release followed Higuchi kinetics (R² = 0.900), indicating diffusion-driven release, with the Korsmeyer–Peppas model (n = 0.88) suggesting anomalous transport. Antibacterial studies showed inhibition of Staphylococcus aureus (MIC = 250 µg/mL) and Escherichia coli (MIC = 500 µg/mL). In vivo anti-inflammatory testing demonstrated significant edema reduction (p < 0.05) using a carrageenan-induced rat paw model. These results support the potential of Melissa nanoemulgel as a stable and effective topical therapeutic for inflammatory and microbial skin disorders. Full article

(This article belongs to the Special Issue Properties and Structure of Plant-Based Emulsion Gels)

22 pages, 2940 KB

Open AccessArticle

Hybrid Alginate-Based Polysaccharide Aerogels Microparticles for Drug Delivery: Preparation, Characterization, and Performance Evaluation

by Mohammad Alnaief, Balsam Mohammad, Ibrahem Altarawneh, Dema Alkhatib, Zayed Al-Hamamre, Hadeia Mashaqbeh, Khalid Bani-Melhem and Rana Obeidat

Gels 2025, 11(10), 775; https://doi.org/10.3390/gels11100775 (registering DOI) - 26 Sep 2025

Abstract

Hybrid polysaccharide-based aerogels offer significant potential as advanced drug delivery platforms due to their tunable structure, high porosity, and biocompatibility. In this study, aerogel microparticles were synthesized using alginate, pectin, carrageenan, and their hybrid formulations via an emulsion–gelation technique followed by supercritical fluid [...] Read more.

Hybrid polysaccharide-based aerogels offer significant potential as advanced drug delivery platforms due to their tunable structure, high porosity, and biocompatibility. In this study, aerogel microparticles were synthesized using alginate, pectin, carrageenan, and their hybrid formulations via an emulsion–gelation technique followed by supercritical fluid CO₂ extraction. The resulting aerogels exhibit mesoporous structures with specific surface areas ranging from 324 to 521 m²/g and pore volumes between 1.99 and 3.75 cm³/g. Comprehensive characterization (SEM, gas sorption, XRD, TGA, DSC, and FTIR) confirmed that hybridization improved morphological uniformity and thermal stability compared to single polymer aerogels. Ibuprofen was used as a model drug to evaluate loading efficiency and release kinetics. Among all formulations, the alginate/carrageenan (2:1) hybrid showed the highest drug loading efficiency (93.5%) and a rapid release profile (>90% within 15 min), closely matching the performance of commercial ibuprofen tablets. Drug release followed Fickian diffusion, as confirmed by the Korsmeyer–Peppas model (R² > 0.99). These results highlight the potential of hybrid polysaccharide aerogels as vehicles for drug delivery and other fast-acting therapeutic applications. Full article

(This article belongs to the Special Issue Advanced Aerogels: From Design to Application)

20 pages, 2538 KB

Open AccessArticle

Development and Evaluation of Nystatin-Loaded Novasomal Gel for the Treatment of Candida albicans Infection: In Vitro Microbiological and Skin Compatibility Study

by Muhammad Abid Mustafa, Muhammad Fahad, Maryam Mughal, Namra Rasheed, Saad S. Alqahtani and Muhammad Zahid Iqbal

Gels 2025, 11(10), 774; https://doi.org/10.3390/gels11100774 - 25 Sep 2025

Abstract

Candida infections pose a significant health threat, and conventional antifungal drugs like nystatin are limited due to poor solubility, skin permeability, and frequent dosage requirements. Nystatin effectively targets Candida species by disrupting cell membranes, but formulation issues hinder clinical use. Lipid-based vesicular carriers, [...] Read more.

Candida infections pose a significant health threat, and conventional antifungal drugs like nystatin are limited due to poor solubility, skin permeability, and frequent dosage requirements. Nystatin effectively targets Candida species by disrupting cell membranes, but formulation issues hinder clinical use. Lipid-based vesicular carriers, or novasomes, provide controlled, prolonged drug release and enhanced skin penetration. This study focuses on developing nystatin-loaded novasomal gels as an advanced drug delivery system to enhance therapeutic efficacy, bioavailability, and patient compliance. The formulation was prepared using a modified ethanol injection technique, combining stearic acid, oleic acid, Span 60, cholesterol, and Carbopol to produce a stable transdermal gel. Comprehensive in vitro characterization using FTIR, SEM, XRD, and thermal analysis confirmed the chemical compatibility, morphological uniformity, and physical stability of the nystatin-loaded novasomal gel. Entrapment efficiency differed significantly among the formulations (p < 0.05), with F7 achieving the highest value (80%). All formulations maintained pH levels within the skin-friendly range of 5.5 to 7.0. Viscosity measurements, ranging from 3900 ± 110 to 4510 ± 105 cP, confirmed their appropriate consistency for dermal use. Rheological analysis showed a dominant elastic response, as indicated by storage modulus values consistently higher than the loss modulus. Particle size ranged from 4143 to 9570 nm, while PDI values remained below 0.3, reflecting uniform particle distribution. Zeta potential values were strongly negative, supporting physical stability. XRD studies indicated reduced crystallinity of nystatin within the formulations, while FTIR confirmed drug-excipient compatibility. SEM images showed spherical particles within the micrometer range. In vitro release studies demonstrated sustained drug release over 12 h, with F6 releasing the highest amount. The novasomal gel formulations-maintained stability for 30 days, with no notable alterations in pH, viscosity, or entrapment efficiency. Antifungal evaluation showed a larger inhibition zone (23 ± 2 mm) compared with the plain drug solution (15 ± 1.6 mm), while the MIC value was reduced (4.57 µg/mL), indicating greater potency. Skin irritation assessment in rats revealed only minor, temporary erythema, and the calculated Primary Irritation Index (0.22) confirmed a non-irritant profile. These findings suggest that the developed novasomal gel offers a promising approach for enhancing the treatment of fungal infections by enabling prolonged drug release, minimizing dosing frequency, and improving patient compliance. Full article

(This article belongs to the Special Issue Antimicrobial Gels and Related Process Technologies)

► Show Figures

Graphical abstract

15 pages, 2066 KB

Open AccessArticle

Spectroscopic and Rheological Characterization of Polyvinyl Alcohol/Hyaluronic Acid-Based Systems: Effect of Polymer Ratio and Riboflavin on Hydrogel Properties

by Iulia Matei, Marius Alexandru Mihai, Sorina-Alexandra Leau, Ludmila Aricov, Anca Ruxandra Leonties, Elvira Alexandrescu and Gabriela Ionita

Gels 2025, 11(10), 773; https://doi.org/10.3390/gels11100773 - 25 Sep 2025

Abstract

We report a systematic investigation on the physicochemical properties of polymer systems consisting of polyvinyl alcohol (PVA) and hyaluronic acid (HA) mixed in various volume ratios (1/4, 2/3, 1/1, 3/2, and 4/1). At PVA/HA ratios above 1/1, in the presence of glutaraldehyde and [...] Read more.

We report a systematic investigation on the physicochemical properties of polymer systems consisting of polyvinyl alcohol (PVA) and hyaluronic acid (HA) mixed in various volume ratios (1/4, 2/3, 1/1, 3/2, and 4/1). At PVA/HA ratios above 1/1, in the presence of glutaraldehyde and divinyl sulfone as crosslinking agents, hydrogels are formed. Their swelling behavior is dependent on the polymer ratio, with the highest water uptake determined for PVA/HA 4/1. The in situ generation of reactive oxygen species (HO^• radicals) under UV-A irradiation, in the presence of riboflavin as a photoinitiator, is evidenced by electron paramagnetic resonance (EPR) spectroscopy. The diffusion of small paramagnetic molecules across the interface of two PVA/HA 4/1 gel pieces placed in direct contact reveals the occurrence of molecular exchange, which could indicate some degree of self-repair of the hydrogel network. When the paramagnetic moiety is attached to the HA polymer by spin labeling, the absence of diffusion demonstrates the stability of the crosslinked HA chains within the PVA/HA network. The structural modifications induced by crosslinking, by the presence of riboflavin, and by exposure to UV-A light, and the resulting alterations in the mechanical behavior of the hydrogels are monitored by infrared spectroscopy and rheology. Only a slight decrease in the viscoelastic moduli values is noted, indicating that the formation of HO^• radicals has minimal impact on the macroscopic properties of the hydrogels. Full article

(This article belongs to the Special Issue State-of-the-Art Gel Research in Romania)

► Show Figures

Figure 1

21 pages, 5935 KB

Open AccessArticle

A Superhydrophobic Gel Fracturing Fluid with Enhanced Structural Stability and Low Reservoir Damage

by Qi Feng, Quande Wang, Naixing Wang, Guancheng Jiang, Jinsheng Sun, Jun Yang, Tengfei Dong and Leding Wang

Gels 2025, 11(10), 772; https://doi.org/10.3390/gels11100772 - 25 Sep 2025

Abstract

Conventional fracturing fluids, while essential for large-volume stimulation of unconventional reservoirs, often induce significant reservoir damage through water retention and capillary trapping. To address this problem, this study developed a novel superhydrophobic nano-viscous drag reducer (SN-DR), synthesized through a multi-monomer copolymerization and silane [...] Read more.

Conventional fracturing fluids, while essential for large-volume stimulation of unconventional reservoirs, often induce significant reservoir damage through water retention and capillary trapping. To address this problem, this study developed a novel superhydrophobic nano-viscous drag reducer (SN-DR), synthesized through a multi-monomer copolymerization and silane modification strategy, which enhances structural stability and minimizes reservoir damage. The structure and thermal stability of SN-DR were characterized by FT-IR, ¹H NMR, and TGA. Rheological evaluations demonstrated that the gel fracturing fluid exhibits a highly stable three-dimensional network structure, with a G′ maintained at approximately 3000 Pa and excellent shear recovery under cyclic stress. Performance tests showed that a 0.15% SN-DR achieved a drag reduction rate of 78.1% at 40 L/min, reduced oil–water interfacial tension to 0.91 mN·m⁻¹, and yielded a water contact angle of 152.07°, confirming strong hydrophobicity. Core flooding tests revealed a flowback rate exceeding 50% and an average permeability recovery of 86%. SEM and EDS indicated that the gel formed nanoscale, tightly packed papillary structures on core surfaces, enhancing roughness and reducing water intrusion. The study demonstrates that gel fracturing fluid enhances structural stability, alters wettability, and mitigates water-blocking damage. These findings offer a new strategy for designing high-performance fracturing fluids with integrated drag reduction and reservoir protection properties, providing significant theoretical insights for improving hydraulic fracturing efficiency. Full article

(This article belongs to the Section Gel Applications)

► Show Figures

Figure 1

17 pages, 3942 KB

Open AccessArticle

Transparent Elastic Wound Dressing Gel Supporting Drug Release: Synergistic Effects of Poly(Vinyl Alcohol)/Chitosan Hybrid Matrix

by Lifei Chen, Ningning Yuan, Zhenjiang Tan, Jianwei Zhang, Lishi Zhang, Wenwei Tang, Cheng Chen and Donghai Lin

Gels 2025, 11(10), 771; https://doi.org/10.3390/gels11100771 - 25 Sep 2025

Abstract

Wound infection is one of the most critical factors affecting the healing process. Therefore, the development of wound dressings with excellent antibacterial effects has become a research hotspot in the current academic field. We prepared AgNPs (silver nanoparticles) via a redox method, combined [...] Read more.

Wound infection is one of the most critical factors affecting the healing process. Therefore, the development of wound dressings with excellent antibacterial effects has become a research hotspot in the current academic field. We prepared AgNPs (silver nanoparticles) via a redox method, combined them with Poly(vinyl alcohol)/chitosan (PVA/CS), and dried the mixture into a film to fabricate a silver-loaded hydrogel film dressing with excellent antibacterial properties. Uniaxial tensile tests on the samples revealed that the prepared film dressings exhibited good mechanical properties, preventing fracture caused by external forces. Protein adsorption experiments indicated their favorable protein adsorption performance, which can adsorb microorganisms on the external surface of the dressing. By leveraging the bactericidal mechanism of AgNPs, the dressing achieves efficient antibacterial effects. Additionally, the dressing prepared by this method features good transparency, facilitating routine observation of the wound area without removing the dressing and maintaining a sterile environment for an extended period. Finally, we verified the drug loading and drug release capabilities of the dressing, and found that it has good drug loading capacity and drug release effect. This preliminarily proves its effectiveness and provides more possibilities for subsequent research on composite drugs. This study provides new insights for exploring the clinical application of multifunctional silver-loaded wound dressings. Full article

(This article belongs to the Special Issue Designing Gels for Wound Dressing (2nd Edition))

► Show Figures

Figure 1

22 pages, 5342 KB

Open AccessArticle

Effect of Protonated Media on Dye Diffusion in Chitosan–Cellulose-Based Cryogel Beads

by Alfredo García-González, Rosa Elvira Zavala-Arce, Pedro Avila-Pérez, Jacob Josafat Salazar-Rábago, Jose Luis Garcia-Rivas and Carlos Eduardo Barrera-Díaz

Gels 2025, 11(10), 770; https://doi.org/10.3390/gels11100770 - 25 Sep 2025

Abstract

Synthetic dyes are increasingly relevant pollutants due to their widespread use and discharge into water bodies. This study examines how the solution pH affects the morphology of chitosan–cellulose cryogel (Ch-C-EGDE) and its impact on dye transport to adsorption sites. Adsorption tests with dyes [...] Read more.

Synthetic dyes are increasingly relevant pollutants due to their widespread use and discharge into water bodies. This study examines how the solution pH affects the morphology of chitosan–cellulose cryogel (Ch-C-EGDE) and its impact on dye transport to adsorption sites. Adsorption tests with dyes Y5, R2, and B1 over a pH range of 2–12 revealed optimal performance at pH 2.5. High hydronium ion concentrations significantly improved adsorption capacities (945–1605 mg/g), with a hierarchy B1 > R2 > Y5 at 250 mg/L initial concentration. The dependence of the dye adsorption on the acidic pH of the solution suggests that there is a mechanism of adsorption by electrostatic forces due mainly to the protonation of the amino group (NH₃⁺). During the dye adsorption studies, a decrease in the diameter of the cryogel beads was observed, as well as a possible “zipper effect” in the pores of the Ch-C-EGDE cryogel beads, which depends on the pH at which the anionic molecules of the dyes attract the positively charged chitosan-based adsorbent walls, which physically closes the pores and results in a decrease in pore size as well as a geometric and/or load-bearing impediment. The experimental data fitted well with the pseudo-second-order kinetic models and the Sips isotherm model, indicating multilayer and heterogeneous adsorption behavior. In the Sips model, a value of n > 1 was obtained, which confirms favorable adsorption conditions and suggests strong dye-adsorbent material interactions, especially at higher dye concentrations. Full article

(This article belongs to the Special Issue Cellulose Gels: Properties and Prospective Applications)

► Show Figures

Graphical abstract

19 pages, 3800 KB

Open AccessArticle

The Size Effects of Modified Nano-Silica on the Physical Properties of Resorcinol-Poly(acrylamide-co-2-acrylamido-2-methylpropanesulfonic Acid) Gels in Harsh Reservoir Conditions

by Xun Zhong, Yuxuan Yang, Jiating Chen, Yudan Dong, Sheng Lei, Hui Zhao, Hong He and Lifeng Chen

Gels 2025, 11(10), 769; https://doi.org/10.3390/gels11100769 - 24 Sep 2025

Viewed by 9

Abstract

Nano-silica is widely used to enhance gel properties, but its size, concentrations, and aggregation behaviors all matter. The influencing rules of these factors remain unclear especially in harsh reservoir conditions. This study presented a comprehensive investigation into the gelation, rheological, and plugging properties [...] Read more.

Nano-silica is widely used to enhance gel properties, but its size, concentrations, and aggregation behaviors all matter. The influencing rules of these factors remain unclear especially in harsh reservoir conditions. This study presented a comprehensive investigation into the gelation, rheological, and plugging properties of phenolic polymer gels reinforced by modified nano-silica (GSNP) of different sizes and concentrations in harsh reservoir conditions. Specifically, the nano-silica was modified with a highly soluble silane, and gel properties were evaluated through rheological, differential scanning calorimetry (DSC), and sandpack flooding tests. The results showed that the incorporation of GSNP prolonged the gelation time, enhanced gel strength, and improved stability, allowing the gelation solution to enter deeper into the formation while maintaining long-time effectiveness. The optimal gel system was obtained with 0.4 wt.% GSNP-30, under which condition the storage modulus increased by approximately 14 times, and the content of non-freezable bound water more than doubled. This system exhibited plugging efficiency exceeding 80% in formations with permeabilities ranging from 1000 to 6000 millidarcy and enhanced the oil recovery factor by over 25%. The reinforcement mechanisms were attributed to the adsorption of GSNP onto polymer chains and its role in filling the gel matrix, which enhanced polymer hydrophilicity, suppressed polymer aggregation/curling, prevented ion penetration, and promoted the formation of a more uniform gel network. Careful optimization of nanoparticle size and concentration was essential to avoid the detrimental effects due to nanoparticle overfilling and aggregation. The novelty of this study lies in the practicable formulation of thermal and salt-tolerant gel systems with facile modified nano-silica of varying sizes and the systematic study of size and concentration effects. These findings offer practical guidance for tailoring nanoparticle parameters to cater for high-temperature and high-salinity reservoir conditions. Full article

(This article belongs to the Section Gel Applications)

► Show Figures

Figure 1

19 pages, 4766 KB

Open AccessArticle

Experimental Study on Migration Characteristics and Profile Control Performance of Gel Foam in Fractured-Vuggy Reservoir

by Yan Xin, Binfei Li, Jingyu Zhang, Bo Wang, Aojue Liu and Zhaomin Li

Gels 2025, 11(10), 768; https://doi.org/10.3390/gels11100768 - 24 Sep 2025

Viewed by 57

Abstract

Gel foam exhibits excellent applicability in fractured-vuggy reservoirs, effectively plugging flow channels and enhancing oil recovery. However, due to the harsh high-temperature environment and the complex and variable fracture-vuggy structure in reservoirs, gel foam may undergo structural changes during its migration, which can [...] Read more.

Gel foam exhibits excellent applicability in fractured-vuggy reservoirs, effectively plugging flow channels and enhancing oil recovery. However, due to the harsh high-temperature environment and the complex and variable fracture-vuggy structure in reservoirs, gel foam may undergo structural changes during its migration, which can affect its flow properties and plugging efficiency. Therefore, investigating the migration characteristics of gel foam in fractured reservoirs through visual experiments is of significant practical importance. In this study, migration experiments with different foam systems were conducted using the visualized vuggy model. The migration stability of foam was characterized by combining the sweep range and liquid drainage rate, and the impact of temperature on the migration characteristics of gel foam was explored. Additionally, a profile control experiment was performed using the fractured-vuggy network model, analyzing and summarizing its mechanisms for enhancing oil recovery in fractured-vuggy reservoirs. The results showed that, in the vuggy model, compared with ordinary foam and polymer foam, gel foam showed a lower drainage rate, higher foam retention rate and wider sweep range, and could form stable plugging in fractured-vuggy reservoirs. An increased temperature accelerated the thermal expansion of gas and changes in liquid film characteristics, which led to the expansion of foam migration speed and sweep range. Although a high temperature increased the liquid drainage rate of foam, it was still lower than 3%, and the corresponding foam retention rate was higher than 97%. In addition, the gel foam had a strong profile control ability, which effectively regulated the gas migration path and improved the utilization degree of remaining oil. Compared with the first gas flooding, the recovery of subsequent gas flooding was increased by 18.85%, and the final recovery of the model reached 81.51%. Comprehensive analysis revealed that the mechanism of enhanced oil recovery by gel foam mainly included density control, foam regeneration, flow redirection, stable plugging, and deep displacement by stable gel foam. These mechanisms worked synergistically to contribute to increased recovery. The research results fully demonstrate the application advantages of gel foam in fractured-vuggy reservoirs. Full article

(This article belongs to the Special Issue Polymer Gels for the Oil and Gas Industry)

► Show Figures

Figure 1

15 pages, 4141 KB

Open AccessArticle

Fabrication and Properties of Chitosan/Calcium Polyphosphate Fibre Composite Biological Scaffold

by Xiaohu Qiang, Zhu Hu, Wang Liu and Dajian Huang

Gels 2025, 11(10), 767; https://doi.org/10.3390/gels11100767 - 24 Sep 2025

Viewed by 51

Abstract

Natural biomaterials are widely used in the construction of cartilage tissue engineering due to their excellent biocompatibility, easy degradation, and ability to degrade products to be absorbed by the human body. However, due to their poor mechanical properties, it is usually necessary to [...] Read more.

Natural biomaterials are widely used in the construction of cartilage tissue engineering due to their excellent biocompatibility, easy degradation, and ability to degrade products to be absorbed by the human body. However, due to their poor mechanical properties, it is usually necessary to composite them with other materials to prepare biological scaffolds that meet the expected requirements. This study used freeze-drying technology to introduce calcium polyphosphate fibres (CPPFs) into a chitosan (CS) matrix to prepare composite scaffolds with better performance. CPPF was used as a filler and inorganic skeleton in the CS/CPPF composite to improve the properties of the CS-based scaffold. With little change in porosity, the compressive strength of the CS/CPPF composite scaffold increased from 0.172 MPa of chitosan to 0.332 MPa with the increase in CPPF addition. The water absorption rate of the composite scaffold decreased from 1297.42% to 935.37%. In vitro degradation experiments revealed that CPPF accelerated the degradation of the scaffold and generated calcium phosphate and nano-hydroxyapatite compounds during the degradation process. According to our cytotoxicity testing, the CS/CPPF composite scaffolds exhibited good biocompatibility and could enhance cell proliferation. This method of incorporating CPPF into CS provides important reference values for the application of CPPF in other natural bone tissue engineering scaffold materials. Full article

(This article belongs to the Special Issue Synthesis and Application of Aerogel (2nd Edition))

► Show Figures

Graphical abstract

17 pages, 2112 KB

Open AccessArticle

Highly Sensitive Optical Fiber Pb²⁺ Concentration Sensor Based on HEMA/AM/SA Interpenetrating Polymer Network (IPN) Hydrogel

by Ning Wang, Ming He, Longjiao Wang, Chuanjie Lei, Linyufan Xiao, Yingjie Li and Shuan Liu

Gels 2025, 11(10), 766; https://doi.org/10.3390/gels11100766 - 23 Sep 2025

Viewed by 84

Abstract

An optical fiber sensor based on a HEMA/AM/SA interpenetrating polymer network (IPN) hydrogel is proposed for monitoring the concentration of Pb²⁺. The Fabry–Perot interference cavity is constructed from a single-mode fiber, a ceramic ferrule, and an IPN hydrogel layer. P (HEMA [...] Read more.

An optical fiber sensor based on a HEMA/AM/SA interpenetrating polymer network (IPN) hydrogel is proposed for monitoring the concentration of Pb²⁺. The Fabry–Perot interference cavity is constructed from a single-mode fiber, a ceramic ferrule, and an IPN hydrogel layer. P (HEMA co AM)/SA IPN hydrogel films were prepared by a step-by-step crosslinking method, which had good mechanical properties, swelling properties, and Pb²⁺ adsorption capacity. The Pb²⁺ concentration changes cause the interference spectrum shift of the sensor. By monitoring the wavelength shift under different Pb²⁺ concentrations, the sensor sensitivity in the range of 0~1 ppm Pb²⁺ concentration in solution is 5.0743 nm/ppm with 0.994 linearity. The influence of different proportions of IPN hydrogel on the performance of the sensor was studied. In the range of 10–90% HEMA, higher sensitivity is obtained by a small weight ratio of HEMA/AM. The sensor stability, repeatability, selectivity, dynamic response, and temperature response are also investigated in experiments. Experimental results demonstrate that the proposed sensor exhibits good stability, sensitivity, repeatability, and selectivity. Owing to its compact structure, straightforward fabrication, low cost, and good sensing performance, this sensor shows strong potential for application in monitoring Pb²⁺ concentrations. Full article

(This article belongs to the Special Issue Gel-Based Materials for Intelligent Sensors and Self-Powered Nanogenerators)

► Show Figures

Figure 1

21 pages, 19117 KB

Open AccessArticle

Biofunctional Carboxymethyl Chitosan Hydrogel Incorporating Hyaluronic Acid and RGD Peptides for Accelerated Wound Repair

by Shuyue Wang, Qing Yang, Jiren Xu, Youshiqi Zhou, Xiaoqing Tian, Wenhui Wu, Jeevithan Elango and Xiaozhen Diao

Gels 2025, 11(10), 765; https://doi.org/10.3390/gels11100765 - 23 Sep 2025

Viewed by 222

Abstract

Carboxymethyl chitosan (CMC)-based hydrogels have emerged as promising candidates for wound dressing applications due to their excellent biocompatibility and tunable physicochemical properties. In this study, a novel hydrogel functionalized with hyaluronic acid (HA) and RGD peptides (RGD) was fabricated and evaluated for its [...] Read more.

Carboxymethyl chitosan (CMC)-based hydrogels have emerged as promising candidates for wound dressing applications due to their excellent biocompatibility and tunable physicochemical properties. In this study, a novel hydrogel functionalized with hyaluronic acid (HA) and RGD peptides (RGD) was fabricated and evaluated for its structural characteristics and wound-healing potential. Using CMC as the base matrix and EDC/NHS as crosslinking agents, four hydrogel variants were fabricated: CMC gel, CMC-HA gel, CMC-RGD gel, and CMC-HA-RGD gel. The preliminary cell compatibility experiment identified the optimal formulation as 1% CMC, 0.9% HA, and 0.02 mg/mL RGD, crosslinked with 1 vol% EDC and 0.05 wt% NHS. Scanning electron microscopy showed a porous architecture (100–400 μm), conducive to fibroblast viability and proliferation. Zeta potential measurements (|ζ| > 30 mV) indicated colloidal stability of the hydrogel system. Fourier-transform infrared spectroscopy confirmed successful crosslinking and integration of HA and RGD via hydrogen bonding and electrostatic interactions, forming a stable three-dimensional network. Thermogravimetric analysis revealed enhanced thermal stability upon HA/RGD incorporation. CCK-8 assays demonstrated significantly improved cell viability with HA/RGD loading (p < 0.05), while Ki-67 immunofluorescence confirmed enhanced fibroblast proliferation, with the CMC-HA-RGD gel showing the most pronounced effect. In vitro scratch assay results demonstrated that the CMC-HA-RGD hydrogel dressing significantly enhanced cellular migration compared to other carboxymethyl chitosan-based hydrogel groups (p < 0.05). The observed statistically significant improvement in cell migration rate versus controls underscores the distinctive enhancement of synergistic HA and RGD modification in accelerating cellular migration and facilitating wound repair. Collectively, these findings suggest that the CMC-HA-RGD hydrogel possesses favorable physicochemical and biological properties and holds strong potential as an advanced wound dressing for the treatment of chronic and refractory wounds. Full article

(This article belongs to the Special Issue Polysaccharide Gels for Biomedical and Environmental Applications)

► Show Figures

Graphical abstract

27 pages, 13129 KB

Open AccessArticle

Biofunctional Polyvinyl Alcohol/Xanthan Gum/Gelatin Hydrogel Dressings Loaded with Curcumin: Antibacterial Properties and Cell Viability

by María José Rivera, Alejandro Cament, Manuel Ahumada, Teresa Corrales, Verónica García, Jesús L. Pablos, Javiera Osorio, Giselle Ramos-González, Leslie Vargas-Saturno, Marcelo Ezquer and J. Andrés Ortiz

Gels 2025, 11(10), 764; https://doi.org/10.3390/gels11100764 - 23 Sep 2025

Viewed by 228

Abstract

This study explores the development of biocompatible hydrogel dressings incorporating curcumin as an alternative antibacterial agent. In this context, hydrogels were prepared using polyvinyl alcohol, xanthan gum, gelatin, and curcumin as a therapeutic component. FTIR spectroscopy confirmed the successful incorporation of curcumin into [...] Read more.

This study explores the development of biocompatible hydrogel dressings incorporating curcumin as an alternative antibacterial agent. In this context, hydrogels were prepared using polyvinyl alcohol, xanthan gum, gelatin, and curcumin as a therapeutic component. FTIR spectroscopy confirmed the successful incorporation of curcumin into the hydrogel matrix, while release profiles demonstrated sustained release. Mechanical testing indicated that xanthan gum reduced elongation and strength in hydrogels, while the combination of xanthan gum and gelatin increased stiffness without loss of elasticity. Curcumin had no major effect on the tensile and rheological properties, preserving the structural integrity of the hydrogels. The hydrogels demonstrated antibacterial activity against Pseudomonas aeruginosa and Staphylococcus aureus ATCC strains, as well as multidrug methicillin-resistant Staphylococcus aureus (MRSA) clinical isolates. Biocompatibility was confirmed through viability assays with immortalized human keratinocytes (HaCaT) and adult human dermal fibroblasts (HDFa), showing no acute cytotoxic effects after 48 h of exposure. Their effective action against clinically relevant bacteria and high cytocompatibility position these hydrogels as promising candidates for infection management and antibiotic resistance mitigation in wound care applications. Full article

(This article belongs to the Special Issue Hydrogel for Tissue Engineering and Biomedical Therapeutics (2nd Edition))

► Show Figures

Figure 1

12 pages, 395 KB

Open AccessArticle

Mitigating Quality Deterioration of Reduced-Fat Pork Sausages During Cold Storage via Resistant Starch Incorporation: Gel Properties and Protein Conformation Study

by Guanghui Liu, Jingchao Fan, Li Wang, Minghui Liang, Chun Xie and Zhuangli Kang

Gels 2025, 11(10), 763; https://doi.org/10.3390/gels11100763 - 23 Sep 2025

Viewed by 132

Abstract

This study investigated the changes in pH, water retention, color, texture characteristics, protein conformation, thiobarbituric acid reactive substances (TBARSs), total volatile basic nitrogen (TVB-N), and total plate count in reduced-fat sausages. It explored the quality differences between sausages with and without the addition [...] Read more.

This study investigated the changes in pH, water retention, color, texture characteristics, protein conformation, thiobarbituric acid reactive substances (TBARSs), total volatile basic nitrogen (TVB-N), and total plate count in reduced-fat sausages. It explored the quality differences between sausages with and without the addition of resistant starch during storage at 4 °C over a period of 1 to 30 days. The results indicated that TBARS and TVB-N values significantly increased (p < 0.05) with the extension of refrigeration time, and the α-helix and β-sheet structures were transformed into β-turn and random coil structures, leading to a significant decrease in the pH, L* and a* values, texture characteristics, and chewiness of all sausages, as well as a significant increase in storage loss and centrifugation loss. Under the same refrigeration time, the sausage with added resistant starch exhibited better water retention and texture characteristics compared to the treatment without resistant starch. Additionally, the TBARS and TVB-N values were significantly lower (p < 0.05) in the former. Therefore, the incorporation of resistant starch can effectively slow down the deterioration of gel properties and the increase in total bacterial count in reduced-fat sausages during refrigeration. Full article

► Show Figures

Figure 1

Journal Menu

Journal Browser

Gels, Volume 11, Issue 10 (October 2025) – 14 articles

Further Information

Guidelines

MDPI Initiatives

Follow MDPI