Fluorescent silica MCM-41 nanoparticles based on flavonoids: Direct post-doping encapsulation and spectral characterization

Flavones and flavonols are naturally-occurring organic molecules with interesting biological, chemical photophysical properties. In recent years their interaction silica surfaces has received increasing attention. this work, the flavonol 3-hydroxyflavone (3HF) flavone 7-hydroxyflavone (7HF) have been encapsulated in MCM-41 mesoporous nanoparticles (NP) via a post-doping procedure, photophysics characterized by both steady state time-resolved spectroscopic techniques. Both flavonoid-doped NPs resulted to be highly fluorescent, even after two months of exposure air at room temperature. UV light irradiation results moderate decrease fluorescence quantum yield. Complementary UV–Vis experiments 3HF 7HF solutions TD-DFT calculations simulate absorption emission spectra carried out order better rationalize exact nature emitting species. Whereas for 3HF-doped tautomer green predominates, 7HF-doped is likely arise from cationic or phototautomeric form flavonoid. The show that fluorophore-based fluorescent can easily obtained procedure represent first step towards development simple strategy encapsulation flavonoids other molecules. • Luminescent based were synthetized procedure. Flavonoid-doped static remain luminescent Photostability tests more stable inside than solution. performed absorption/fluorescence identify precise