Rhodamine-based near-infrared probe for emission detection of ATP in lysosomes in living cells

Abstract

A new near infrared fluorescent probe was designed and prepared to detect ATP and target lysosomes in cells. The non-fluorescent probe was turned on during the interaction with ATP, affording a 115-fold increase in fluorescence intensity. The colorless probe turned purple upon interaction with ATP. The probe displayed high sensitivity and selectivity toward ATP compared with other biomolecules, such as AMP, ADP, GMP, and CMP. Such significant spectroscopic changes derive from a structural change of the probe’s spirocyclic moiety to its ring-opened form. This occurs through electrostatic and π,π-stacking interactions between the probe and ATP. This probe was also used in selective lysosome staining and for real-time ATP level monitoring. It exhibits great advantages in cell imaging studies, such as excellent photostability, low cytotoxicity, and good cell membrane permeability.