Environment-Dependent Ultrafast Photodynamics of Aurone Derivatives for the Photoprotection of Agrochemicals

Abstract

Derivatised aurones, based on phytochemical flavonoids, were synthesised and studied using steady-state and ultrafast spectroscopy techniques. Aurones’ strong ultraviolet (UV) and visible absorption, in addition to being found in abundance in fruits, vegetables and flowers, makes them ideal photoprotection candidates for agrochemicals. Agrochemicals are well known to exhibit poor photostability, and the addition of photoprotectants to their formulations thus increases their longevity, and thereby environmental sustainability. The results presented here shed light on the complex ultrafast and long term photodynamics of five nature-inspired derivatives in solution and on a wax surface, the latter designed to mimic the cuticle of a plant leaf. This study finds markedly different relaxation mechanisms between these condensed phase environments, highlighting the importance of studying photoprotectants in their real-world environments. These findings inspire the development of safe and effective photoprotectants for agrochemicals.