Paper-based sensing of phytotoxicant gossypol in aqueous media through turn-on visible-light emitting lanthanide-luminescence.

Gossypol, a phytotoxicant in cotton-seed oil, has been found to sensitize Tb(III)-luminescence in a supramolecular hydrogel. Based on this observation, a paper-based sensor has been developed to detect gossypol with a limit of detection (LOD) of 2.9 nM. This is the first report of water-based detection with the highest sensitivity involving turn-on time-gated luminescence. This method was also able to sense gossypol in commercial crude cotton-seed oil.