Alginate gels: Chemistry, gelation mechanisms, and therapeutic applications with a focus on GERD treatment.

Alginate, a natural polysaccharide derived primarily from marine algae, has become popular in biomedical research due to its versatile gelation properties and biocompatibility. This review explores the chemistry, gelation mechanisms, and therapeutic applications of alginate gels, with a particular focus on their role in gastroesophageal reflux disease (GERD) management. Alginate's structure, comprised of guluronic and mannuronic acid blocks, allows for gel formation by ionic cross-linking with divalent cations like calcium ions, generating a stable "egg-box" structure. The effects of pH, temperature, and ion concentration on gelation are explored, as well as other gel forms such as in situ and heat-sensitive gels. Alginate is widely used in the medical and pharmaceutical areas to promote tissue engineering through cell encapsulation and scaffolding, as well as in drug delivery systems for controlled and targeted release. In GERD therapy, alginate produces a gel raft that inhibits acid reflux, providing an effective alternative to proton pump inhibitors. Alginate-based products have demonstrated clinical success, strengthening alginate's medicinal promise. The review also discusses alginate-related issues, such as source variability and stability, as well as innovative modifications to improve treatment effects. These improvements establish alginate as a potential material for customized medication and tailored delivery systems.