Exploring β-glucan as a micro-nano system for oral delivery targeted the colon.

The critical role of oral colon-specific delivery systems (OCDDS) is important for delivering active agents to the colon and rectum specifically via the oral route. The use of micro/nanostructured OCDDS further improves drug stability, bioavailability, and retention time, leading to enhanced therapeutic effects. However, designing micro/nanoscale OCDDSs is challenging due to pH changes, enzymatic degradation, and systemic absorption and metabolism. Biodegradable natural polysaccharides are a promising solution to these problems, and β-glucan is one of the most promising natural polysaccharides due to its unique structural features, conformational flexibility, and specific processing properties. This review covers the diverse chemical structures of β-glucan, its benefits (biocompatibility, easy modification, and colon-specific degradation), and various β-glucan-based micro/nanosized OCDDSs, as well as their drawbacks. The potential of β-glucan offers exciting new opportunities for colon-specific drug delivery.