Phenoxazine-based covalent organic frameworks as a turn-off fluorescent probe for trace water detection in organic solvents.

Phenoxazine-based COFs (TFPB-DAPO-COF and TFPT-DAPO-COF) were synthesized and exhibited wider characteristic intramolecular charge transfer (ICT) than parent phenoxazine. Phenoxazine-based COFs can form hydrogen bonds with water molecules in aprotic solvents, weakening the ICT effect, and leading to a proportional decrease in fluorescence intensity. Therefore, DAPO-COFs can be used as a tool for the detection of water molecules.

Highly fluorescent carbon dots from coix seed for the determination of furazolidone and temperature.

In this work, blue emission fluorescent carbon dots (CDs) were fabricated by using the hydrothermal strategy from coix seed for the first time. We found that the prepared CDs possessed many excellent characteristics including excitation-dependent properties, good solubility and strong photostability. The optimal excitation and emission wavelength of CDs were 363 and 435 nm, respectively.