A new poly(norbornene)-based sensor for fluorescent ratiometric sensing of adenosine 5′-triphosphate

A new fluorescent poly(norbornene)-based copolymer (P1) containing rhodamine B in the spirocyclic ring form and 1,8-naphthalimide fluorophores has been designed and synthesized for sensing and detection of ATP. In aqueous solution, probe P1 can self-assemble into nanostructured aggregates and exhibit 1,8-naphthalimide-based green emission. After interaction with ATP, energy transfer from 1,8-naphthalimide donor to rhodamine B acceptor occurs, with the fluorescent color changing from green to red. The detection limit of P1 to ATP was calculated to be 0.34 μM. Probe P1 also possesses good photostability and biocompatibility, and has been successfully utilized for the detection of ATP level in living cells.