Invitrogen™ Monomeric Cyanine Nucleic Acid Stains

High-affinity, low-background fluorescent probes for ultrasensitive nucleic acid detection

Invitrogen™ Monomeric Cyanine Nucleic Acid Stains are a family of cell-impermeant, high-sensitivity fluorescent dyes for double-stranded nucleic acid (dsDNA) detection in microscopy, flow cytometry, electrophoresis, and solid-support assays. These dyes exhibit low background in unbound form and undergo 20- to 1800-fold fluorescence enhancement upon binding DNA, producing exceptionally bright and specific nuclear staining.

With strong dsDNA binding (micromolar dissociation constants) and distinct spectral properties, the monomeric cyanine stains are ideal for nuclear counterstaining, dead-cell discrimination, and nucleic acid visualization across the visible spectrum. YO-PRO™-1 is unique among the series in being able to enter apoptotic cells, making it a convenient apoptosis indicator.

Available Dyes & Spectral Properties

Key Features

• High affinity – Strong dsDNA binding (Kd in micromolar range)
• Low background – Negligible fluorescence when unbound
• Large fluorescence enhancement – 20–1800× increase upon DNA binding
• Bright fluorescence – High extinction coefficients and quantum yields
• Spectral diversity – Coverage across blue, green, orange, and far-red channels
• Specialized applications – YO-PRO-1 for apoptosis detection; TO-PRO-3 for far-red nuclear counterstaining

Applications

• Nuclear counterstaining in fluorescence microscopy
• Flow cytometry for cell viability and apoptosis discrimination
• Nucleic acid detection in gel and capillary electrophoresis
• Solid-support nucleic acid visualization
• Multiparametric assays with minimal spectral overlap

Specifications

Invitrogen™ Monomeric Cyanine Nucleic Acid Stains deliver ultrasensitive, spectrally diverse, and low-background nucleic acid labeling for high-resolution imaging, precise flow cytometry analysis, and robust gel-based assays. Their high affinity for dsDNA and range of excitation/emission options make them ideal for multiplex experiments, viability assays, and nuclear staining in fixed-cell workflows.