Selective photoluminescence enhancement of red emitted surface modified poly(p-phenylenediamine) dots: An ultra-sensitive anion photoluminescence sensor for F− in vitro

The weak interactions between anions and common functional groups make it difficult for the development of anion photoluminescence sensors. In this work, we report an ultra-sensitive anion photoluminescence (PL) sensor for F − based on triethylene glycol monomethyl ether modified poly(p-phenylenediamine) dots (TPPDs). Due to the PET process in excited TPPDs, no obvious PL behavior can be observed in TPPDs. Due to the fast photoinduced electron transfer (PET) process in excited TPPDs, no obvious photoluminescence behavior can be observed: however, the PET process can be cut off in the presence of F − and TPPDs show bright red PL. The detection limit of this system is 2 × 10 −10 M, which is much lower than most other reported detection methods. Compared with traditional “ON-OFF” PL sensors, such an “OFF-ON” PL detection system shows higher value in practical applications. The detection system exhibits superior photostability and high selectivity for F − . We also demonstrate the successful F − detection in vitro based on TPPDs.