Self-reporting of payload release in polymer coatings based on the inner filter effect†
We demonstrate successful monitoring of payload release from nanoparticles and in coatings by the inner filter effect. The payload 8-hydroxyquinoline (8HQ) was encapsulated in fluorescent polymer nanoparticles. In the presence of the payload, the fluorescence of the polymer is quenched while dequenching occurs upon release of payload. The fluorescent polymer and 8HQ can be simultaneously embedded in coatings deposited on metal substrates. Upon corrosion of the metal, a change of color occurs, indicating the release of 8HQ from the coatings. This in situ detection of payload release in solid matrix is a promising strategy for observing corrosion at early stages and monitoring the progress of payload diffusion.