One water-soluble fluorescent perylene diimide [N,N′-bi(L-glutamic amine) perylene-3,4,9,10-tetracarboxylic diimide](PTCDG)derived from the raw material 3,4,9,10-perylenetetracarboxy anhydride was synthesized and characterized by IR and 1H NMR spectra.A novel fluorescent switch was constructed based on PTCDG in presence of diamagnetic Fe2+or paramagnetic Fe3+.The switch turns off in presence of paramagnetic Fe3+owing to the PET quench,while it turns on in presence of diamagnetic Fe2+because of the absence of the PET quench.The magnetism reversability between Fe2+and Fe3+could be used to detect hydrogen peroxide and vitamin C. |