Polymer Hydrogels: Synthesis, Characterization and Applications

A special issue of Polymers (ISSN 2073-4360). This special issue belongs to the section "Polymer Networks".

Deadline for manuscript submissions: 15 July 2024 | Viewed by 6439

Special Issue Editors

Department of Physical & Environmental Sciences, University of Toronto Scarborough, 1265 Military Trail, Toronto, ON M1C1A4, Canada
Interests: NMR/MRI; polymers; hydrogels; SAXS/WAXS; biomaterials

E-Mail Website
Guest Editor
School of Chemistry, University College Dublin, Dublin, Ireland
Interests: NMR; nanomaterials; nanostructural dynamics

E-Mail Website
Guest Editor
Netherlands Organisation for Scientific Research (NWO), DUBBLE@ESRF, BP CS 40220, 38043 Grenoble, France
Interests: supramolecular chemistry; polymer processing; biopolymers; structure-properties relationship; x-ray scattering; SAXS/WAXS; soft matter; polymer physics
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Defined as 3D water-retaining networks made from hydrophilic polymer chains, hydrogels have recently attracted widespread attention in both scientific and industrial fields owing to their exceptional promise in a wide range of applications, such as tissue engineering and drug delivery. The formation of hydrogel can involve physical, chemical, and hybrid bonding. They can be produced via different routes, such as freeze–thaw processes, solution mixing, radical polymerization, and suspension polymerization. As a result of its unique feature (mimic extracellular matrix, biocompatibility, and biodegradability), the new-generation “smart hydrogels” can respond to external stimuli (e.g., pH, temperature, mechanical force, and light) that leads to a wide application of hydrogel materials (e.g., bio-sensors).

This Special Issue focuses on the synthesis, characterization, and application of novel polymer-based hydrogel systems. We invite researchers to share their latest findings in the form of research articles, rapid communications, and reviews. 

Dr. Bing Wu
Dr. Dermot Brougham
Dr. Daniel Hermida-Merino
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. Polymers is an international peer-reviewed open access semimonthly 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 2700 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

  • advanced materials
  • bio-hybrid hydrogels
  • drug delivery systems
  • cross-linking structures
  • the advanced characterization of hydrogels
  • tissue engineering hydrogels
  • physical hydrogels
  • natural hydrogels
  • gelation mechanism
  • the novel application of hydrogels

Published Papers (5 papers)

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

Research

12 pages, 4117 KiB  
Article
Stretchable, Adhesive, and Biocompatible Hydrogel Based on Iron–Dopamine Complexes
by Celine Lee, He-Shin Huang, Yun-Ying Wang, You-Sheng Zhang, Rajan Deepan Chakravarthy, Mei-Yu Yeh, Hsin-Chieh Lin and Jeng Wei
Polymers 2023, 15(22), 4378; https://doi.org/10.3390/polym15224378 - 10 Nov 2023
Viewed by 1037
Abstract
Hydrogels’ exceptional mechanical strength and skin-adhesion characteristics offer significant advantages for various applications, particularly in the fields of tissue adhesion and wearable sensors. Herein, we incorporated a combination of metal-coordination and hydrogen-bonding forces in the design of stretchable and adhesive hydrogels. We synthesized [...] Read more.
Hydrogels’ exceptional mechanical strength and skin-adhesion characteristics offer significant advantages for various applications, particularly in the fields of tissue adhesion and wearable sensors. Herein, we incorporated a combination of metal-coordination and hydrogen-bonding forces in the design of stretchable and adhesive hydrogels. We synthesized four hydrogels, namely PAID-0, PAID-1, PAID-2, and PAID-3, consisting of acrylamide (AAM), N,N′-methylene-bis-acrylamide (MBA), and methacrylic-modified dopamine (DA). The impact of different ratios of iron (III) ions to DA on each hydrogel’s performance was investigated. Our results demonstrate that the incorporation of iron–dopamine complexes significantly enhances the mechanical strength of the hydrogel. Interestingly, as the DA content increased, we observed a continuous and substantial improvement in both the stretchability and skin adhesiveness of the hydrogel. Among the hydrogels tested, PAID-3, which exhibited optimal mechanical properties, was selected for adhesion testing on various materials. Impressively, PAID-3 demonstrated excellent adhesion to diverse materials and, combined with the low cytotoxicity of PAID hydrogel, holds great promise as an innovative option for biomedical engineering applications. Full article
(This article belongs to the Special Issue Polymer Hydrogels: Synthesis, Characterization and Applications)
Show Figures

Figure 1

13 pages, 4542 KiB  
Article
Facile Synthesis of Self-Adhesion and Ion-Conducting 2-Acrylamido-2-Methylpropane Sulfonic Acid/Tannic Acid Hydrogels Using Electron Beam Irradiation
by Hee-Woong Park, Nam-Gyu Jang, Hyun-Su Seo, Kiok Kwon and Seunghan Shin
Polymers 2023, 15(18), 3836; https://doi.org/10.3390/polym15183836 - 20 Sep 2023
Viewed by 741
Abstract
Tannic acid (TA) can be used as an additive to improve the properties of hydrogels, but it acts as a radical scavenger, which hinders radical polymerization. In this study, we successfully and easily synthesized a TA-incorporated 2-acrylamido-2-methylpropanesulfonic acid (AMPS) hydrogel using an electron [...] Read more.
Tannic acid (TA) can be used as an additive to improve the properties of hydrogels, but it acts as a radical scavenger, which hinders radical polymerization. In this study, we successfully and easily synthesized a TA-incorporated 2-acrylamido-2-methylpropanesulfonic acid (AMPS) hydrogel using an electron beam (E-beam) in a one-pot process at room temperature. TA successfully grafted onto AMPS polymer chains under E-beam irradiation, but higher TA content reduced grafting efficiency and prevented hydrogel formation. Peel strength of the AMPS hydrogel increased proportionally with TA, but cohesive failure and substrate residue occurred above 1.25 phm (parts per 100 g of AMPS) TA. Tensile strength peaked at 0.25 phm TA but decreased below the control value at 1.25 phm. Tensile elongation exceeded 2000% with TA addition. Peel strength varied significantly with substrate type. The wood substrate had the highest peel strength value of 150 N/m, while pork skin had a low value of 11.5 N/m. However, the addition of TA increased the peel strength by over 300%. The ionic conductivity of the AMPS/TA hydrogel increased from 0.9 S/m to 1.52 S/m with TA content, while the swelling ratio decreased by 50% upon TA addition and increased slightly thereafter. Full article
(This article belongs to the Special Issue Polymer Hydrogels: Synthesis, Characterization and Applications)
Show Figures

Graphical abstract

12 pages, 4887 KiB  
Article
Hydrogelation of Regenerated Silk Fibroin via Gamma Irradiation
by Peerapat Thongnuek, Sorada Kanokpanont, Pimpon Uttayarat and Siriporn Damrongsakkul
Polymers 2023, 15(18), 3734; https://doi.org/10.3390/polym15183734 - 12 Sep 2023
Viewed by 814
Abstract
Gamma irradiation, which is one of the more conventional sterilization methods, was used to induce the hydrogelation of silk fibroin in this study. The physical and chemical characteristics of the irradiation-induced silk fibroin hydrogels were investigated. Silk fibroin solution with a concentration greater [...] Read more.
Gamma irradiation, which is one of the more conventional sterilization methods, was used to induce the hydrogelation of silk fibroin in this study. The physical and chemical characteristics of the irradiation-induced silk fibroin hydrogels were investigated. Silk fibroin solution with a concentration greater than 1 wt% formed hydrogel when irradiated by gamma rays at a dose of 25 or 50 kGy. The hydrogel induced by 50 kGy of radiation was more thermally stable at 80 °C than those induced by 25 kGy of radiation. When compared to the spontaneously formed hydrogels, the irradiated hydrogels contained a greater fraction of random coils and a lower fraction of β-sheets. This finding implies that gelation via gamma irradiation occurs via other processes, in addition to crystalline β–sheet formation, which is a well-established mechanism. Our observation suggests that crosslinking and chain scission via gamma irradiation could occur in parallel with the β–sheet formation. The irradiation-induced hydrogels were obtained when the solution concentration was adequate to support the radiation crosslinking of the silk fibroin chains. This work has, therefore, demonstrated that gamma irradiation can be employed as an alternative method to produce chemical-free, random coil-rich, and sterilized silk fibroin hydrogels for biomedical applications. Full article
(This article belongs to the Special Issue Polymer Hydrogels: Synthesis, Characterization and Applications)
Show Figures

Figure 1

13 pages, 3061 KiB  
Article
A New Optimization Strategy of Highly Branched Poly(β-Amino Ester) for Enhanced Gene Delivery: Removal of Small Molecular Weight Components
by Yinghao Li, Xianqing Wang, Zhonglei He, Zishan Li, Melissa Johnson, Bei Qiu, Rijian Song, Sigen A, Irene Lara-Sáez, Jing Lyu and Wenxin Wang
Polymers 2023, 15(6), 1518; https://doi.org/10.3390/polym15061518 - 18 Mar 2023
Cited by 6 | Viewed by 1970
Abstract
Highly branched poly(β-amino ester) (HPAE) has become one of the most promising non-viral gene delivery vector candidates. When compared to other gene delivery vectors, HPAE has a broad molecular weight distribution (MWD). Despite significant efforts to optimize HPAE targeting enhanced gene delivery, the [...] Read more.
Highly branched poly(β-amino ester) (HPAE) has become one of the most promising non-viral gene delivery vector candidates. When compared to other gene delivery vectors, HPAE has a broad molecular weight distribution (MWD). Despite significant efforts to optimize HPAE targeting enhanced gene delivery, the effect of different molecular weight (MW) components on transfection has rarely been studied. In this work, a new structural optimization strategy was proposed targeting enhanced HPAE gene transfection. A series of HPAE with different MW components was obtained through a stepwise precipitation approach and applied to plasmid DNA delivery. It was demonstrated that the removal of small MW components from the original HPAE structure could significantly enhance its transfection performance (e.g., GFP expression increased 7 folds at w/w of 10/1). The universality of this strategy was proven by extending it to varying HPAE systems with different MWs and different branching degrees, where the transfection performance exhibited an even magnitude enhancement after removing small MW portions. This work opened a new avenue for developing high-efficiency HPAE gene delivery vectors and provided new insights into the understanding of the HPAE structure–property relationship, which would facilitate the translation of HPAEs in gene therapy clinical applications. Full article
(This article belongs to the Special Issue Polymer Hydrogels: Synthesis, Characterization and Applications)
Show Figures

Graphical abstract

12 pages, 1859 KiB  
Article
High-Linearity Hydrogel-Based Capacitive Sensor Based on Con A–Sugar Affinity and Low-Melting-Point Metal
by Ruixue Yin, Jizhong Xin, Dasheng Yang, Yang Gao, Hongbo Zhang, Zhiqin Qian and Wenjun Zhang
Polymers 2022, 14(20), 4302; https://doi.org/10.3390/polym14204302 - 13 Oct 2022
Cited by 4 | Viewed by 1441
Abstract
Continuous glucose monitoring (CGM) plays an important role in the treatment of diabetes. Affinity sensing based on the principle of reversible binding to glucose does not produce intermediates, and the specificity of concanavalin A (Con A) to glucose molecules helps to [...] Read more.
Continuous glucose monitoring (CGM) plays an important role in the treatment of diabetes. Affinity sensing based on the principle of reversible binding to glucose does not produce intermediates, and the specificity of concanavalin A (Con A) to glucose molecules helps to improve the anti-interference performance and long-term stability of CGM sensors. However, these affinity glucose sensors have some limitations in their linearity with a large detection range, and stable attachment of hydrogels to sensor electrodes is also challenging. In this study, a capacitive glucose sensor with high linearity and a wide detection range was proposed based on a glucose-responsive DexG–Con A hydrogel and a serpentine coplanar electrode made from a low-melting-point metal. The results show that within the glucose concentration range of 0–20 mM, the sensor can achieve high linearity (R2 = 0.94), with a sensitivity of 33.3 pF mM−1, and even with the larger glucose concentration range of 0–30 mM the sensor can achieve good linearity (R2 = 0.84). The sensor also shows resistance to disturbances of small molecules, good reversibility, and long-term stability. Due to its low cost, wide detection range, high linearity, good sensitivity, and biocompatibility, the sensor is expected to be used in the field of continuous monitoring of blood glucose. Full article
(This article belongs to the Special Issue Polymer Hydrogels: Synthesis, Characterization and Applications)
Show Figures

Figure 1

Back to TopTop