A short review on polysaccharide-based nanocomposite adsorbents for separation and biomedical applications

Polysaccharides such as chitosan, alginate, cellulose, and carrageenan have emerged as promising adsorbents due to their biodegradability, abundant availability, and diverse chemical functionality. These biopolymers exhibit promising performance for adsorption of a wide range of pollutants including heavy metals (e.g., lead, cadmium), organic dyes (e.g., methylene blue, methyl orange), and even pathogenic microorganisms. However, inherent hydrophilicity and poor mechanical properties limit their broader application in environmental and biomedical fields. As an effective way to address the issues, recent advancements have focused on the incorporation of nanoparticles (e.g., metal oxides, carbon nanotubes and clays) into polysaccharides to obtain nanocomposite films. Generally, these nanocomposites offer enhanced surface area, tunable porous network, and improved chemical and mechanical resistances for adsorption and biomedical applications. The current review gives a focused overview of the recent progresses in polysaccharide-based nanocomposites, with particular attention to their fabrication methods, adsorption capacity and mechanism, and diverse applications in water purification, drug delivery, and antimicrobial treatments. Critical challenges such as the optimization of nanoparticle dispersion and the environmental impacts of nanocomposite biodegradation are also discussed to pave the road for the future research in this promising field.