Near-infrared fluorescence marker (NIRF marker)

Near-infrared fluorescence markers are synthetic molecules (dyes) that emit fluorescence in the near-infrared (NIR) range (typically 650–900 nm or longer) upon excitation with NIR light. This property provides deeper tissue penetration, reduced background signal, and higher sensitivity than visible-range fluorescent markers, making NIRF markers valuable for in vivo imaging, surgical guidance, and real-time monitoring of biological processes. Common NIRF dyes include indocyanine green (ICG), IRDye 800CW, and heptamethine-based molecules. These markers are not therapeutic targets themselves but are frequently conjugated to antibodies, peptides, or drugs to enable targeted imaging of tissues, tumors, or biological processes. They are used in a variety of applications including cancer detection, sentinel lymph node mapping, vascular and lymphatic imaging, and image-guided surgery.

Other names

near-infrared fluorescent probeNIRF probeNIR fluorescent dyenear-infrared fluorophoreNIR dye

No intrinsic mechanism of drug action; function via fluorescence emission upon NIR excitation. If conjugated, activity depends on the linked molecule.