Application of atomic force microscopy in microscopic analysis of polysaccharide

Background: Polysaccharides are one of the major group of bioactive macromolecular derived from plants, bacteria, fungi and seaweeds. Atomic force microscopy (AFM), a type of scanning probe microscopy, is a powerful technology to visualize biopolymers, such as polysaccharides and proteins, up to a single molecular level in near-native conditions. Scope and approach: This review gives a brief description of AFM technology involved in polysaccharide research in addition to discussion of factors that might influence polysaccharide imaging. More importantly, its contribution to research progress of a variety of well characterized polysaccharides, including pectin, xanthan, carrageenan, curdlan, scleroglucan, xyloglucan, arabinoxylan, starch, etc., and the detailed nanostructure information was summarized. Key findings and conclusions: AFM provides a unique insight into polysaccharide studies in terms of morphological features and molecular characteristics, such as heights (diameters), width, contour length, end-to-end distance, polydispersity, etc. Besides, other promising aspects included probing molecular motion and assemblies, as well as visualizing conformation behavior under different conditions.