Influence of ionic liquids on protein and polysaccharide: advances in solubility, structure and interactions

Ionic liquids (ILs), as a class of "green solvents" with distinctive physicochemical properties, demonstrate great potential for regulating the solubility, structure, and functional characteristics of biological macromolecules. Proteins and polysaccharides, two important biomacromolecules, can form functional materials with diverse application potential through their mutual interactions. Research has shown that ILs can bind to specific sites on proteins or polysaccharides, altering their structure and aggregation state. This binding effectively regulates the interaction between proteins and polysaccharides, leading to the formation of complexes with enhanced functional properties. Understanding and controlling the physicochemical properties of biomacromolecules in ILs is crucial. This enables the manufacture of diverse functional biomaterials, including drug carriers, food packaging films, and other novel biomaterials. This review aims to provide an overview of the effects of ILs on proteins, polysaccharides, and their complexes, with a focus on recent advances in solubility, structure, and interactions. Future research will concentrate on elucidating the regulatory mechanisms behind the interactions between ILs and proteins or polysaccharides. Additionally, it will aim to develop more efficient IL systems that are environmentally friendly, specifically by improving biodegradability and reducing toxicity to expand their applications in biomedicine and food science.