1 O 2 -Relevant Afterglow Luminescence of Chlorin Nanoparticles for Discriminative Detection and Isotopic Analysis of H 2 O and D 2 O.

Discriminative detection between D 2 O and H 2 O is important for diverse fields but challenging due to their high similarity in chemical and physical properties. Current molecular sensors for D 2 O detection generally rely on the spectral change of fluorophores with suitable p K a in response to D 2 O and H 2 O with slightly different pH acidity. Herein, we report a new and facile D 2 O sensor by using singlet oxygen ( 1 O 2 )-relevant afterglow luminescence of chlorin e4 nanoparticles (Ce4-NPs) to achieve distinguishable detection between D 2 O and H 2 O. As 1 O 2 is a key initiator involved in the afterglow luminescence process, it displays a 22-fold longer lifetime in D 2 O relative to H 2 O and thereafter generates more dioxetane intermediates after laser irradiation to lead to ultimate afterglow brightness of Ce4-NPs in D 2 O. In addition, Ce4-NPs are capable of quantitatively detecting the amount of H 2 O in D 2 O with a limit of detection (LOD) of 1.45%. Together, this study broadens the utility of afterglow materials and presents a facile strategy for isotopic purity analysis of heavy water.