Recent Trends in Application of Amphiphilic Block Copolymer Based Hydrogels

Abstract

Amphiphilic block copolymer based hydrogels (ABCHs) with hydrophobic and hydrophilic blocks can be constructed by employing synthetic as well as natural polymers. One of the crosslinking methods is covalent crosslinking, in which both hydrophilic and hydrophobic parts are chemically crosslinked together. In the present chapter, we have explored the ABCHs synthesized through free radical solution polymerization technique, in which, instead of using conventional crosslinking agents, the monomers contribute towards a hydrophilic polymer segment as well as crosslinking. The properties of these hydrogels, such as biocompatibility, low toxicity, maintained biodegradability, self-assembly, and response to environmental stimuli, have also been detailed. Since the hydrogels have appropriate mechanical properties and can regulate the release of hydrophobic drugs, they have found several uses in the biomedical field. A hydrophobic drug can be uniformly loaded into ABCHs because of a suitable connection between the hydrophobic drug and the hydrophobic polymer chain. They are also capable of delivering both hydrophilic and hydrophobic drugs because of the presence of both segments. We have further detailed the ABCHs widely used in drug delivery, wound dressing, tissue engineering, and various biomedical applications.

Introduction

Amphiphilic block copolymers (ABCs) are polymers composed of both hydrophilic (water-attracting) and hydrophobic (water-repelling) segments. This unique structure allows them to self-assemble into diverse nanostructures with tunable morphologies, useful for biomedical applications. Hydrophilic blocks provide biocompatibility and swelling ability, while hydrophobic blocks create nanoscopic cavities for carrying insoluble substances.

Amphiphilic block copolymer-based hydrogels (ABCHs) are 3D networks formed by combining these segments, exhibiting high water absorption, biostability, and controlled drug release. Their properties, such as stiffness, swelling rate, and degradability, can be tailored by adjusting polymer composition, crosslinking, and synthesis conditions. However, challenges include complex synthesis, high costs, and sometimes low drug loading efficiency.

Synthesis methods primarily involve free radical polymerization, ionic crosslinking, or chemical coupling, enabling formation of chemically crosslinked hydrogels with stable networks. Amphiphilic multiblock hydrogels help prevent phase separation, enhancing material uniformity.

Properties of ABCHs include:

• Mechanical strength adjustable for specific uses (e.g., tissue engineering, drug delivery),

• Biocompatibility allowing safe interaction with biological systems,

• Self-assembly into hierarchical structures useful for encapsulating and releasing drugs.

Applications mainly focus on:

• Drug delivery systems, where hydrogels can load and release both hydrophilic and hydrophobic drugs in response to stimuli like temperature or pH,

• Tissue engineering, where hydrogels serve as scaffolds mimicking natural tissues to promote cell growth and tissue regeneration,

• Wound healing and other biomedical uses due to their multifunctionality.

Conclusion

In this chapter, the mechanical features of hydrogels that spontaneously swell are explained by their association of amphiphilic polymers. These hydrogels are utilized in the fields of pharmaceuticals, biocompatibility, and other environmental applications. The most suitable properties of hydrogels employed along with medicines, crosslinking mechanism, fabrication processes, design considerations of hydrogel engineering, and wound healing have been covered in this chapter, along with an overview of the many types of hydrogels on wound inflammation. Subsequently, it is essential to examine novel possibilities for amphiphilic block copolymers in order to broaden the range of hydrogel applications. Hydrogels made of hydrophilic and hydrophobic polymers have found extensive use in the biomedical field because of their good mechanical qualities, biocompatibility, and biodegradability. Hydrogels based on amphiphilic block copolymers are networks that have both hydrophilic and hydrophobic segments. These networks typically develop through effective free radical crosslinking polymerisation with hydrophilic and hydrophobic monomers. Utilised in drug delivery, tissue engineering, and wound healing, ABCHs are hydrogels composed of hydrophilic and hydrophobic monomers that have adjustable strength, compatibility, and self-assembly.

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Copyright

Copyright © 2025 Anmol Kumar, Shubhangi Pandey, Krishna Kumar, S. Krishnamoorthi, Kranthikumar Tungala. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.