Gel-Based Materials: Preparations and Characterization (2nd Edition)

A special issue of Gels (ISSN 2310-2861). This special issue belongs to the section "Gel Analysis and Characterization".

Deadline for manuscript submissions: 15 November 2024 | Viewed by 19232

Special Issue Editors


E-Mail Website
Guest Editor
Osaka Research Institute of Industrial Science and Technology, Morinomiya Center, Osaka 536-8553, Japan
Interests: hydrogels; low-molecular-weight gels; supramolecular gels; self-assembly; surfactants
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Chiba Institute of Science, Faculty of Pharmacy, Choshi-shi, Chiba 388-0025, Japan
Interests: hydrogels; low-molecular-weight gels; self-assembly; surfactants; emulsion; TDDS
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

We are grateful to all the authors, reviewers, and readers for their responses to the first edition of “Gel-Based Materials: Preparations and Characterization”. You can access these articles for free via the link: Gel-Based Materials: Preparations and Characterization

Gel-based materials have important applications in our daily lives. Conventionally, they have been widely used in cosmetics, foods, and paints. However, recently, they have been used in a broader range of fields such as energy, the environment, and medicine, partly due to the development of low-molecular-weight gelators that utilize molecular self-assembly and commonly used polymer gelators. This increase in gelation methods is likely because gel-based materials are much easier to control based on their rheological properties. Hence, remarkable progress has been made in developing gels with various functions, such as separation, extraction, and stimulus/biomolecule responses. Thus, this Special Issue invites original papers and review articles on the preparations and characterization of gel-based materials with various functions. Topics include:

  • Supramolecular gels (low-molecular-weight gels);
  • Lamellar gel networks (α-form hydrated crystals);
  • Liquid crystal gels;
  • Ionic gels;
  • Gels with separation and extraction functions;
  • Stimuli- or biomolecule-responsive gels;
  • Emulsion gels.

In addition to the above, we welcome submissions on gel-based materials with various functions.

Dr. Rie Kakehashi
Dr. Yuji Yamashita
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Gels is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2100 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • supramolecular gels (low-molecular-weight gels)
  • lamellar gel networks (α-form hydrated crystals)
  • liquid crystal gels
  • ionic gels
  • gels with separation and extraction functions
  • stimuli- or biomolecule-responsive gels
  • emulsion gels

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Related Special Issue

Published Papers (10 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

Jump to: Review

16 pages, 7227 KiB  
Article
Use of Chitosan–Iron Oxide Gels for the Removal of Cd2+ Ions from Aqueous Solutions
by Eduardo Mendizábal, Nely Ríos-Donato, Minerva Guadalupe Ventura-Muñoz, Rosaura Hernández-Montelongo and Ilse Paulina Verduzco-Navarro
Gels 2024, 10(10), 630; https://doi.org/10.3390/gels10100630 - 30 Sep 2024
Viewed by 547
Abstract
High-quality water availability is substantial for sustaining life, so its contamination presents a serious problem that has been the focus of several studies. The presence of heavy metals, such as cadmium, is frequently studied due to the increase in the contamination levels caused [...] Read more.
High-quality water availability is substantial for sustaining life, so its contamination presents a serious problem that has been the focus of several studies. The presence of heavy metals, such as cadmium, is frequently studied due to the increase in the contamination levels caused by fast industrial expansion. Cadmium ions were removed from aqueous solutions at pH 7.0 by chitosan–magnetite (ChM) xerogel beads and chitosan–FeO (ChF) xerogel beads in batch systems. Kinetic studies were best modeled by the Elovich model. The adsorption isotherms obtained showed an inflection point suggesting the formation of a second layer, and the BET model adjusted to liquid–solid systems was adequate for the description of the experimental data. Maximum uptake capacities of 36.97 ± 0.77 and 28.60 ± 2.09 mg Cd/g xerogel were obtained for ChM and ChF, respectively. The studied composites are considered promising adsorbent materials for removing cadmium ions from aqueous systems. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Graphical abstract

21 pages, 7675 KiB  
Article
Analysis of Structural Changes of pH–Thermo-Responsive Nanoparticles in Polymeric Hydrogels
by Lazaro Ruiz-Virgen, Miguel Angel Hernandez-Martinez, Gabriela Martínez-Mejía, Rubén Caro-Briones, Enrique Herbert-Pucheta, José Manuel del Río and Mónica Corea
Gels 2024, 10(8), 541; https://doi.org/10.3390/gels10080541 - 20 Aug 2024
Viewed by 1083
Abstract
The pH- and thermo-responsive behavior of polymeric hydrogels MCcoMA have been studied in detail using dynamic light scattering DLS, scanning electron microscopy SEM, nuclear magnetic resonance (1H [...] Read more.
The pH- and thermo-responsive behavior of polymeric hydrogels MCcoMA have been studied in detail using dynamic light scattering DLS, scanning electron microscopy SEM, nuclear magnetic resonance (1H NMR) and rheology to evaluate the conformational changes, swelling–shrinkage, stability, the ability to flow and the diffusion process of nanoparticles at several temperatures. Furthermore, polymeric systems functionalized with acrylic acid MC and acrylamide MA were subjected to a titration process with a calcium chloride CaCl2 solution to analyze its effect on the average particle diameter Dz, polymer structure and the intra- and intermolecular interactions in order to provide a responsive polymer network that can be used as a possible nanocarrier for drug delivery with several benefits. The results confirmed that the structural changes in the sensitive hydrogels are highly dependent on the corresponding critical solution temperature CST of the carboxylic (–COOH) and amide (–CONH2) functional groups and the influence of calcium ions Ca2+ on the formation or breaking of hydrogen bonds, as well as the decrease in electrostatic repulsions generated between the polymer chains contributing to a particle agglomeration phenomenon. The temperature leads to a re-arrangement of the polymer chains, affecting the viscoelastic properties of the hydrogels. In addition, the diffusion coefficients D of nanoparticles were evaluated, showing a closeness among with the morphology, shape, size and temperature, resulting in slower diffusions for larger particles size and, conversely, the diffusion in the medium increasing as the polymer size is reduced. Therefore, the hydrogels exhibited a remarkable response to pH and temperature variations in the environment. During this research, the functionality and behavior of the polymeric nanoparticles were observed under different analysis conditions, which revealed notable structural changes and further demonstrated the nanoparticles promising high potential for drug delivery applications. Hence, these results have sparked significant interest in various scientific, industrial and technological fields. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

15 pages, 6449 KiB  
Article
Development and Characterization of Gelatin-Based Hydrogels Containing Triblock Copolymer and Phytic Acid
by Njomza Ajvazi, Ingrid Milošev, Romana Cerc Korošec, Peter Rodič and Bojan Božić
Gels 2024, 10(5), 294; https://doi.org/10.3390/gels10050294 - 25 Apr 2024
Viewed by 1501
Abstract
In recent research, significant interest has been directed towards gelatin-based hydrogels due to their affordable price, extensive availability, and biocompatibility, making them promising candidates for various biomedical applications. The development and characterization of novel hydrogels formed from varying ratios of gelatin, triblock copolymer [...] Read more.
In recent research, significant interest has been directed towards gelatin-based hydrogels due to their affordable price, extensive availability, and biocompatibility, making them promising candidates for various biomedical applications. The development and characterization of novel hydrogels formed from varying ratios of gelatin, triblock copolymer Pluronic F-127, and phytic acid have been presented. Swelling properties were examined at different pH levels. The morphology of hydrogels and their thermal properties were analyzed using scanning electron microscopy (SEM), thermogravimetric analysis (TG), and differential scanning calorimetry (DSC). Fourier-transform infrared (FTIR) analysis of the hydrogels was also performed. The introduction of phytic acid in the hydrogel plays a crucial role in enhancing the intermolecular interactions within gelatin-based hydrogels, contributing to a more stable, elastic, and robust network structure. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

26 pages, 5328 KiB  
Article
Chitosan–Oxidized Pullulan Hydrogels Loaded with Essential Clove Oil: Synthesis, Characterization, Antioxidant and Antimicrobial Properties
by Dana Mihaela Suflet, Marieta Constantin, Irina Mihaela Pelin, Irina Popescu, Cristina M. Rimbu, Cristina Elena Horhogea and Gheorghe Fundueanu
Gels 2024, 10(4), 227; https://doi.org/10.3390/gels10040227 - 26 Mar 2024
Cited by 4 | Viewed by 1798
Abstract
Emulsion hydrogels are promising materials for encapsulating and stabilizing high amounts of hydrophobic essential oils in hydrophilic matrices. In this work, clove oil-loaded hydrogels (CS/OP-C) are synthesized by combining covalent and physical cross-linking approaches. First, clove oil (CO) was emulsified and stabilized in [...] Read more.
Emulsion hydrogels are promising materials for encapsulating and stabilizing high amounts of hydrophobic essential oils in hydrophilic matrices. In this work, clove oil-loaded hydrogels (CS/OP-C) are synthesized by combining covalent and physical cross-linking approaches. First, clove oil (CO) was emulsified and stabilized in a chitosan (CS) solution, which was further hardened by Schiff base covalent cross-linking with oxidized pullulan (OP). Second, the hydrogels were subjected to freeze–thaw cycles and, as a result, the clove oil was stabilized in physically cross-linked polymeric walls. Moreover, due to cryogelation, the obtained hydrogels exhibited sponge-like porous interconnected morphology (160–250 µm). By varying the clove oil content in the starting emulsion and the degree of cross-linking, the hydrogels displayed a high water retention capacity (swelling ratios between 1300 and 2000%), excellent elastic properties with fast shape recovery (20 s) after 70% compression, and controlled in vitro clove oil release in simulated skin conditions for 360 h. Furthermore, the prepared clove oil-loaded hydrogels had a strong scavenging activity of 83% and antibacterial and antifungal properties, showing a bacteriostatic effect after 48 and 72 h against S. aureus and E. coli. Our results recommend the new clove oil-embedded emulsion hydrogels as promising future materials for application as wound dressings. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Graphical abstract

12 pages, 2872 KiB  
Article
Nanogels Based on N,N-Dimethylacrylamide and β-Cyclodextrin Triacrylate for Enhanced Solubility and Therapeutic Efficacy of Aripiprazole
by Siyka Stoilova, Dilyana Georgieva, Rositsa Mihaylova, Petar D. Petrov and Bistra Kostova
Gels 2024, 10(4), 217; https://doi.org/10.3390/gels10040217 - 22 Mar 2024
Cited by 1 | Viewed by 1609
Abstract
Aripiprazole (ARZ) is a medication used for the treatment of various diseases such as schizophrenia, bipolar disorder, major depressive disorder, autism, and Tourette’s syndrome. Despite its therapeutic benefits, ARZ is characterized by a poor water solubility which provoked the development of various delivery [...] Read more.
Aripiprazole (ARZ) is a medication used for the treatment of various diseases such as schizophrenia, bipolar disorder, major depressive disorder, autism, and Tourette’s syndrome. Despite its therapeutic benefits, ARZ is characterized by a poor water solubility which provoked the development of various delivery systems in order to enhance its solubility. In the present work, a nanoscale drug delivery system based on N,N-dimethylacrylamide (DMAA) and β-cyclodextrin triacrylate (β-CD-Ac3) as potential aripiprazole delivery vehicles was developed. The nanogels were synthesized by free radical polymerization of DMAA in the presence of β-CD-Ac3 as a crosslinking agent and then loaded with ARZ via host-guest inclusion complexation. The blank- and drug-loaded nanogels were evaluated using different methods. Fourier transform infrared (FTIR) spectroscopy was employed to confirm the incorporation of β-CD moieties into the polymer network. Dynamic light scattering (DLS) was used to study the size of the developed systems. The samples exhibited a monomodal particle size distribution and a relatively narrow dispersity index. The hydrodynamic diameter (Dh) of the gels varied between 107 and 129 nm, with a tendency for slightly larger particles as the β-CD-Ac3 fraction increased. Loading the drug into the nanocarrier resulted in slightly larger particles than the blank gels, but their size was still in the nanoscopic range (166 to 169 nm). The release profiles in PBS were studied and a sustained release pattern with no significant burst effect was observed. A cytotoxicity assessment was also conducted to demonstrate the non-toxicity and biocompatibility of the studied polymers. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

17 pages, 4240 KiB  
Article
Fabrication and Characterization of Quad-Component Bioinspired Hydrogels to Model Elevated Fibrin Levels in Central Nervous Tissue Scaffolds
by Ana M. Diaz-Lasprilla, Meagan McKee, Andrea C. Jimenez-Vergara, Swathisri Ravi, Devon Bellamy, Wendy Ortega, Cody O. Crosby, Jennifer Steele, Germán Plascencia-Villa, George Perry and Dany J. Munoz-Pinto
Gels 2024, 10(3), 203; https://doi.org/10.3390/gels10030203 - 17 Mar 2024
Viewed by 1863
Abstract
Multicomponent interpenetrating polymer network (mIPN) hydrogels are promising tissue-engineering scaffolds that could closely resemble key characteristics of native tissues. The mechanical and biochemical properties of mIPNs can be finely controlled to mimic key features of target cellular microenvironments, regulating cell-matrix interactions. In this [...] Read more.
Multicomponent interpenetrating polymer network (mIPN) hydrogels are promising tissue-engineering scaffolds that could closely resemble key characteristics of native tissues. The mechanical and biochemical properties of mIPNs can be finely controlled to mimic key features of target cellular microenvironments, regulating cell-matrix interactions. In this work, we fabricated hydrogels made of collagen type I (Col I), fibrin, hyaluronic acid (HA), and poly (ethylene glycol) diacrylate (PEGDA) using a network-by-network fabrication approach. With these mIPNs, we aimed to develop a biomaterial platform that supports the in vitro culture of human astrocytes and potentially serves to assess the effects of the abnormal deposition of fibrin in cortex tissue and simulate key aspects in the progression of neuroinflammation typically found in human pathologies such as Alzheimer’s disease (AD), Parkinson’s disease (PD), and tissue trauma. Our resulting hydrogels closely resembled the complex modulus of AD human brain cortex tissue (~7.35 kPa), promoting cell spreading while allowing for the modulation of fibrin and hyaluronic acid levels. The individual networks and their microarchitecture were evaluated using confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Human astrocytes were encapsulated in mIPNs, and negligible cytotoxicity was observed 24 h after the cell encapsulation. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Graphical abstract

14 pages, 4068 KiB  
Article
Spray-Dried Chitosan Hydrogel Particles as a Potential Delivery System for Benzydamine Hydrochloride
by Sofia Milenkova, Rita Ambrus, Mahwash Mukhtar, Bissera Pilicheva and Maria Marudova
Gels 2024, 10(3), 189; https://doi.org/10.3390/gels10030189 - 8 Mar 2024
Cited by 1 | Viewed by 1819
Abstract
Chitosan, being a biocompatible and mucoadhesive polysaccharide, is one of the most preferred hydrogel-forming materials for drug delivery. The objectives of the present study are to obtain spray-dried microparticles based on low-molecular-weight chitosan and study their potential application as cargo systems for the [...] Read more.
Chitosan, being a biocompatible and mucoadhesive polysaccharide, is one of the most preferred hydrogel-forming materials for drug delivery. The objectives of the present study are to obtain spray-dried microparticles based on low-molecular-weight chitosan and study their potential application as cargo systems for the orally active drug benzydamine hydrochloride. Three types of particles are obtained: raw chitosan particles (at three different concentrations), cross-linked with sodium tripolyphosphate (NaTPP) particles (at three different chitosan:NaTPP ratios), and particles coated with mannitol (at three different chitosan:mannitol ratios), all of them in the size range between 1 and 10 µm. Based on the loading efficiency and the yields of the formulated hydrogel particles, one model of each type is chosen for further investigation of the effect of the cross-linker or the excipient on the properties of the gel structures. The morphology of both empty and benzydamine hydrochloride-loaded chitosan particles was examined by scanning electron microscopy, and it was quite regular and spherical. Interactions and composition in the samples are investigated by Fourier-transformed infrared spectroscopy. The thermal stability and phase state of the drug and drug-containing polymer matrixes were tested by differential scanning calorimetry and X-ray powdered diffraction, revealing that the drug underwent a phase transition. A drug release kinetics study of the chosen gel-based structures in simulated saliva buffer (pH = 6.8) and mathematical modeling of the process were performed, indicating the Weibull model as the most appropriate one. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

22 pages, 7591 KiB  
Article
Preparation and Mechano-Functional Characterization of PEGylated Fibrin Hydrogels: Impact of Thrombin Concentration
by Clara F. López-León, Ramon Planet and Jordi Soriano
Gels 2024, 10(2), 116; https://doi.org/10.3390/gels10020116 - 1 Feb 2024
Cited by 1 | Viewed by 1488
Abstract
Three-dimensional (3D) neuronal cultures grown in hydrogels are promising platforms to design brain-like neuronal networks in vitro. However, the optimal properties of such cultures must be tuned to ensure a hydrogel matrix sufficiently porous to promote healthy development but also sufficiently rigid for [...] Read more.
Three-dimensional (3D) neuronal cultures grown in hydrogels are promising platforms to design brain-like neuronal networks in vitro. However, the optimal properties of such cultures must be tuned to ensure a hydrogel matrix sufficiently porous to promote healthy development but also sufficiently rigid for structural support. Such an optimization is difficult since it implies the exploration of different hydrogel compositions and, at the same time, a functional analysis to validate neuronal culture viability. To advance in this quest, here we present a combination of a rheological protocol and a network-based functional analysis to investigate PEGylated fibrin hydrogel networks with gradually higher stiffness, achieved by increasing the concentration of thrombin. We observed that moderate thrombin concentrations of 10% and 25% in volume shaped healthy networks, although the functional traits depended on the hydrogel stiffness, which was much higher for the latter concentration. Thrombin concentrations of 65% or higher led to networks that did not survive. Our results illustrate the difficulties and limitations in preparing 3D neuronal networks, and stress the importance of combining a mechano-structural characterization of a biomaterial with a functional one. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Graphical abstract

Review

Jump to: Research

35 pages, 3174 KiB  
Review
Advancements and Challenges in Self-Healing Hydrogels for Wound Care
by Hossein Omidian, Renae L. Wilson and Erma J. Gill
Gels 2024, 10(4), 241; https://doi.org/10.3390/gels10040241 - 1 Apr 2024
Cited by 1 | Viewed by 3117
Abstract
This manuscript explores self-healing hydrogels as innovative solutions for diverse wound management challenges. Addressing antibiotic resistance and tailored wound care, these hydrogels exhibit promising outcomes, including accelerated wound closure and tissue regeneration. Advancements in multifunctional hydrogels with controlled drug release, antimicrobial properties, and [...] Read more.
This manuscript explores self-healing hydrogels as innovative solutions for diverse wound management challenges. Addressing antibiotic resistance and tailored wound care, these hydrogels exhibit promising outcomes, including accelerated wound closure and tissue regeneration. Advancements in multifunctional hydrogels with controlled drug release, antimicrobial properties, and real-time wound assessment capabilities signal a significant leap toward patient-centered treatments. However, challenges such as scalability, long-term safety evaluation, and variability in clinical outcomes persist. Future directions emphasize personalized medicine, manufacturing innovation, rigorous evaluation through clinical trials, and interdisciplinary collaboration. This manuscript features the ongoing pursuit of effective, adaptable, and comprehensive wound care solutions to transform medical treatments and improve patient outcomes. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

29 pages, 2617 KiB  
Review
Advancements in Cellulose-Based Superabsorbent Hydrogels: Sustainable Solutions across Industries
by Hossein Omidian, Arnavaz Akhzarmehr and Sumana Dey Chowdhury
Gels 2024, 10(3), 174; https://doi.org/10.3390/gels10030174 - 29 Feb 2024
Cited by 6 | Viewed by 3555
Abstract
The development of superabsorbent hydrogels is experiencing a transformative era across industries. While traditional synthetic hydrogels have found broad utility, their non-biodegradable nature has raised environmental concerns, driving the search for eco-friendlier alternatives. Cellulose-based superabsorbents, derived from sustainable sources, are gaining prominence. Innovations [...] Read more.
The development of superabsorbent hydrogels is experiencing a transformative era across industries. While traditional synthetic hydrogels have found broad utility, their non-biodegradable nature has raised environmental concerns, driving the search for eco-friendlier alternatives. Cellulose-based superabsorbents, derived from sustainable sources, are gaining prominence. Innovations include biodegradable polymer hydrogels, natural cellulose-chitosan variants, and cassava starch-based alternatives. These materials are reshaping agriculture by enhancing soil fertility and water retention, serving as potent hemostatic agents in medicine, contributing to pollution control, and providing eco-friendly construction materials. Cellulose-based hydrogels also offer promise in drug delivery and hygiene products. Advanced characterization techniques aid in optimizing their properties, while the shift towards circular economy practices further highlights sustainability. This manuscript provides a comprehensive overview of these advancements, highlighting their diverse applications and environmental benefits. Full article
(This article belongs to the Special Issue Gel-Based Materials: Preparations and Characterization (2nd Edition))
Show Figures

Figure 1

Back to TopTop