Bioinspired Strategy for Controlled Polymerization and Photopatterning of Plant Polyphenols

Plant-derived polyphenols have been widely used to design new multifunctional materials for particle and surface modification. The lack of temporal and spatial control over the oxidation and deposition processes, however, limits possible applications of this diverse class of natural compounds. Autoxidation and deposition of phenolic compounds are uncontrollably triggered by basic pH and oxygen. In this project, inspired by the properties of natural antioxidants to scavenge free radicals and reactive oxygen species (ROS), we propose a method to effectively control the autoxidation and deposition of plant phenolic compounds under basic conditions. We demonstrate that natural antioxidants can inhibit autoxidation of plant polyphenols in basic pH in dark environment. However, UV irradiation of these solutions leads to on-demand temporal and spatial polymerization and deposition of polyphenols. This bioinspired method was used to demonstrate the controlled polymerization, and micropatterning on flat surfaces and inside microfluidic channels opening the way to well-defined 2D coatings based on natural polyphenols and introducing a new simple path to the fabrication of bioinspired functional materials, with potential applications in a wide range of fields.