Figure 4.

Dityrosine formation through cross‐linking. a) Chemical structure of dityrosine. b) Fluorescence of resilin in the wing tendon of an adult dragonfly. The right panels show photomicroscopic images of the tendon under white light (up) and ultraviolet light (down). Reproduced with permission.72 Copyright 2005, Nature Publishing Group. c) Schematic representation of the formation of a recombinant mussel adhesive protein‐based bioadhesive via dityrosine bonding using visible light. Reproduced with permission.78 Copyright 2015, Elsevier.