Fluorescence probe for the fast and sensitive detection and imaging of ONOO-via regulation of charge distribution.

A rapid, sensitive and selective ONOO- probe L-C-CH3-Cy5 was developed using a cyanine dye bearing a meso-quinolinium group. The quinolinium group plays a pivotal role in the performance, as it modulates the signal-to-noise ratio and the reactivity of L-C-CH3-Cy5 towards ONOO-, thereby substantially improving both sensitivity and selectivity.