Research of hydrogels based on chitin and chitosan polysaccharide natural polymers has generated great interest as demonstrated by PubMed papers published in the last 5 years – 1639 on chitin hydrogels / 2097 on chitosan hydrogels, especially in biomedical applications, such as tissue regeneration and drug delivery.
Cellulose and chitosan (a chitin derivative) are the most abundant natural polymers on the planet. Recent advances have been realized through R&D of smart hydrogel systems for a variety of innovative biomedical uses.
Chitosan is a natural cationic copolymer which is hydrophilic in nature with ability to degrade via human enzymes resulting in its biocompatibility and biodegradability. These two biological properties are commonly needed for a variety of biomedical applications, including but not limited to tissue engineering and regeneration, drug delivery, wound healing, etc. As a delivery system chitosan-based hydrogels can be formulated for controlled, sensor, or stimuli release of therapeutic ingredients. Like other biopolymers used in hydrogel matrixes, chitosan illicit mucoadhesive characteristics usually through interactions between opposite charges. This for example can enable scaffolds to bind with tissue and precise targeting in drug delivery.
Smart Chitosan Hydrogels
This article examines innovative uses of chitin, chitosan, and cellulose for biomedical uses. Other areas covered;
- Designing molecules capable of promoting molecular aggregation (gelators).
- Formulation to enable one-dimensional hydrogen bonding interactions, such as amides and saccharides.
- Chitosan low molecular weight compounds heated in a solvent to form a supersaturated solution, which after cooling to room temperature can result in a gel through an aggregation process.
- Small molecules organized into a continuous matrix of polymer fibers that can entraps the solvent by surface tension.
- A heterogeneous “solid” matrix obtained with a hierarchical superstructure aggregation that creates chitosan nanoparticle dimensions.
- In situ gelling polymeric matrices in tissue regeneration which can also be serve as injectable hydrogels. They can act as cell vehicles that have the ability to take the shape of the corresponding tissue cavity.
- Cell adhesion can be minimized since cells can directly be incorporated into the injectable solution
