Biomedical and Environmental Applications of Carrageenan-Based Hydrogels: A Review

The need to replace renewable polymers such as marine-based resources with non-biodegradable, plastic polymers has increased due to environmental issues. Carrageenan is a phycocolloid derived from Irish Moss or carrageenan moss, a type of red algae, mainly Chondrus crispus from which the name carrageenan is derived. Due to the wide variety of algae, they can be extracted from, there are variations in the structures of carrageenan, developed from a basic linear sulfated galactose chain. It performs diverse valuable roles through its aptitude to maintain great amounts of water, being able to form a gel at room temperature, metal chelating, and activities. Carrageenan revealed potential bioactive properties, like immunomodulatory, antiviral, antibacterial, anticoagulant, antioxidant, and antitumor actions. As mentioned, this polymer has hydrogel formation capacity, and its gelling ability is applied in various fields such as pharmaceutical sciences, food technology, biotechnology, engineering, etc. This review contains exhaustive information regarding carrageenan structures, extraction methods, the gel formation mechanism, properties, and the recent development in biomedical and environmental applications of carrageenan-based hydrogels. The biomedical applications comprise wound healing, drug delivery, and tissue engineering. In the field of environmental applications, these hydrogels are employed in the elimination of varied aqueous contaminants like dyes, drugs, metals, etc. at the end of the review, several existing challenges and prospects are also described. Graphical Abstract