When research-based teaching labs reveal near-unity multistep energy transfer in common orange STABILO®

In 2020–21, as part of a research-based laboratory course for third-year bachelor students (L3),1 one project on STABILO highlighters revealed an unexpected phenomenon of excitation energy transfer (EET). Guided by curiosity and the desire to understand it more deeply, researchers from different fields collaborated to show that a common commercial orange highlighter ink achieves both direct and multistep EET with near-unity efficiency—94.4%—one of the highest reported in the literature.2 This outstanding performance arises from a stable dispersion of dye-loaded polymer nanoparticles, about 134 nm in size, and the dispersions can also serve as an efficient water-ethanol sensor, based on their different behavior in water and ethanol with almost no EET observed in ethanol (0.3%). This communication will detail the genesis of this discovery and how steady-state and time-resolved spectroscopy, microscopy, and HPLC were used to characterize these unique properties. It will also highlight how innovation can emerge from everyday materials. It will also highlight how everyday materials can lead to innovation by providing a low-cost, readily available system suitable for a wide range of applications.