A Golgi-Targeting and Dual-Color "Turn-On" Probe for Spatially Precise Imaging of Furin

Development of fluorescence probes for highly accurate detection of cancer-related enzyme activity is important in early cancer diagnosis. Herein, we report a Golgi-targeting and dual-color "Turn-On" probe Q-RVRR-DCM for imaging furin with high spatial precision. By integrating the principles of Forster resonance energy transfer and intramolecular charge transfer, the probe was designed to be non-fluorescent. Upon furin cleavage, Q-RVRR-DCM was converted into Q-RVRR and DCM-NH2, turning the dual fluorescence color "On" at 420 and 640 nm without spectral cross-talk. In furin-overexpressing HCT116 cells, QRVRR-DCM showed not only furin-specific, dual-color "Turn-On" fluorescence but also superior colocalization with a Golgi tracker than the single-color "Turn-On" probe RVRR-DCM. We envision that, with the excellent properties of Golgi-targeting and dual fluorescence color "Turn-On", our furin probe Q-RVRR-DCM could be applied for accurate early diagnosis of cancer in the near future.