Figure 1.

A naturally occurring hydrogel secreted by sundew plants. (a) Images of sundew plant (D. spatulata) and the mucilage secreted from the stalked glands on the leaves of sundew plant. (b) AFM images of nano-network architectures obtained in the sundew adhesive. Scale bars represent 5 µm (i) and 2 µm (ii). (c) In vitro tissue culture of sundew plants. Yellow arrow indicates the formed callus tissue. (d) A schematic drawing of the sundew adhesive, which is considered as a naturally occurring hydrogel. (e) Typical glycosyl composition and linkages of the polysaccharides obtained in sundew adhesive. (Online version in colour.)