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Janelia Fluor® HaloTag® Ligands

The Janelia Fluor® HaloTag® Ligands enable characterization of HaloTag® fusions in endogenous cellular settings. The enhanced brightness of the dyes associated with the HaloTag® ligands enables their use in detection and single-molecule imaging studies. Incorporating deuterium into the alkylamino substituents of rhodamines (Janelia FluorX®) and other dyes improves fluorescence quantum yield, inhibits photochemically induced spectral shifts and slows irreparable photobleaching.

Available ligands:

  • Janelia FluorX® 554 HaloTag® Ligand
  • Janelia Fluor® 525 HaloTag® Ligand
  • Janelia Fluor® 635 HaloTag® Ligand
  • Janelia FluorX® 650 HaloTag® Ligand
  • Janelia Fluor® 585 HaloTag® Ligand

Enhanced brightness using Janelia Fluor® HaloTag® Ligands


HaloTag® TMR Ligand.

Cell imaging with Janelia Fluor 549 HaloTag Ligand

Janelia Fluor® 549 HaloTag® Ligand.

In the Literature

A general method to fine-tune fluorophores for live-cell and in vivo imaging

A general method to fine-tune fluorophores for live-cell and in vivo imaging

Learn how these new fluorescent and fluorogenic labels can open new possibilities in fluorescence microscopy in this Nature Methods paper.

Deuteration improves small-molecule fluorophores

Deuteration improves small-molecule fluorophores

Learn how new dyes show improved brightness, inhibit spectral shifts and slow photobleaching in this preprint from bioRxiv.

Optimization and functionalization of red-shifted rhodamine dyes

Optimization and functionalization of red-shifted rhodamine dyes

Discover modified dyes for far-red or near-infrared light in this preprint from bioRxiv.

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