An Overview on Recent Progress of the Hydrogels: From Material Resources, Properties, to Functional Applications

Abstract

Hydrogels, as the most typical elastomer materials with three-dimensional (3D) network structures, have attracted wide attention owing to their outstanding features in fields of sensitive stimulus response, low surface friction coefficient, good flexibility, and bio-compatibility. Because of numerous fresh polymer materials (or polymerization monomers), hydrogels with various structure diversities and excellent properties are emerging, and the development of hydrogels is very vigorous over the past decade. This review focuses on state-of-the-art advances, systematically reviews the recent progress on construction of novel hydrogels utilized several kinds of typical polymerization monomers, and explores the main chemical and physical cross-linking methods to develop the diversity of hydrogels. Following the aspects mentioned above, the classification and emerging applications of hydrogels, such as pH response, ionic response, electrical response, thermal response, biomolecular response, and gas response, are extensively summarized. Finally, this review is done with the promises and challenges for the future evolution of hydrogels and their biological applications.

Bioinspired Hydrogels as Platforms for Life-Science Applications: Challenges and Opportunities

“…Gelation and network formation can be induced in different ways, either through chemical, physical, or combined crosslinking, as it was discussed in recent comprehensive reviews [1,2,4,[18][19][20]30,[55][56][57][58][59][60]. The characteristics of the building blocks influence in high extent the physico-chemical, mechanical, and biological properties of the hydrogels.…”

“…Depending on their nature, crosslinking density, and hydrophilicity of the segments between two crosslinking points, such versatile networks can absorb a high amount of water. From a chemical point of view, the hydrogels can be obtained from natural or synthetic water soluble (co)polymers of various structures and architectures, interpenetrated polymer networks (IPNs), proteins, peptides, clays, multicomponent systems, etc., having different morphologies and functions [1][2][3]. In particular, smart networks able to respond to physical, chemical, and biological stimuli gained much attention for a wide range of applications: tissue engineering [4], bone regeneration [5], controlled-release drug delivery vehicles [6], wound healing [7], soft robotics [8], biosensing [9], intelligent electronics and artificial intelligence [10], actuators [11][12][13], stretched electronic devices [14], hygiene products [15,16], contact lens [17], cosmetics [18], food nutrition and health, food safety and food engineering and processing [19], advanced wastewater treatment [20], catalysis [21][22][23], etc.…”

Smart Internal Bio‐Glues

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] Smart bio-glues for wound healing, tissue adhesion, and other biomedical applications are particularly interesting by exhibiting stimuli-responsive features compared with conventional samples. [14][15][16][17][18][19][20] For example, light-responsive bio-glues with contact-free, spatiotemporal regulation, rigorous tailor, remote control, and other unique advantages have been DOI: 10.1002/advs.202203587 widely used in wound healing, [21] adhesive hemostasis, [22] and tissue adhesion. [23][24][25] Several kinds of smart polymers would undergo a sol-gel transition process upon irradiation by UV or visible light, which could achieve rapid hemostasis, biomimetic tissue engineering, and tissue sealing.…”

Chemical labeling and crosslinking of tobacco mosaic virus via multi-diazonium reagents: examples, applications, and prospects

“…Hydrogels are three-dimensional (3D) networks of hydrophilic polymers joined together by covalent bonds or physical intermolecular attraction. [1][2][3][4][5] The presence of hydrophilic moieties such as amide, carboxyl, amino, and hydroxyl groups scattered along the backbone of the 3D networks contributes to the high hydrophilicity of hydrogels. 2 Many hydrogels have good biocompatibility, [3][4][5] and therefore the biomedical applications of hydrogels have expanded to many fields, including drug delivery, 3 biosensors, 6 wound healing, 7 tissue engineering, 5,8 cell culture, 9 antibacterial materials, 10 and others.…”

“…[1][2][3][4][5] The presence of hydrophilic moieties such as amide, carboxyl, amino, and hydroxyl groups scattered along the backbone of the 3D networks contributes to the high hydrophilicity of hydrogels. 2 Many hydrogels have good biocompatibility, [3][4][5] and therefore the biomedical applications of hydrogels have expanded to many fields, including drug delivery, 3 biosensors, 6 wound healing, 7 tissue engineering, 5,8 cell culture, 9 antibacterial materials, 10 and others. 11 These hydrogel materials can be prepared from different building blocks (e.g., cellulose nanofibrils and peptides) [12][13][14] and using different strategies (Fig.…”