Biotium Introduces Flexible, Time-Saving, and Cost-Effective Fluorescent Labeling for HaloTag® Fusion Proteins

ViaTag™ Haloalkane Ligands streamline workflows in a wide range of colors with lower overall cost compared to other wash-intensive haloalkane ligands.

FREMONT, CA, February 2, 2026 — Biotium, a leading provider of innovative fluorescent reagents and kits for life science research, announces the release of a new line of bright fluorescent ligands designed for flexible labeling of HaloTag® self-labeling protein tags in live or fixed cells. ViaTag™ Haloalkane Ligands are available in 11 fluorescent colors spanning blue to near-infrared, to support a wide range of multicolor imaging and flow cytometry applications. ViaTag™ Haloalkane ligands provide rapid covalent labeling with minimal background and no extensive wash steps for streamlined labeling protocols and lower overall cost.

HaloTag® is a self-labeling protein tag that forms a covalent bond with fluorescent haloalkane ligands for stable, fluorescence-based detection. Biotium’s ViaTag™ Haloalkane Ligands deliver bright, durable labeling that remains robust through fixation, permeabilization, and protein extraction. Offered in both cell membrane–permeant and impermeant formats, ViaTag™ Haloalkane Ligands allow for labeling of intracellular  or cell-surface tagged proteins. ViaTag™ Haloalkane Ligands are supplied as stable, ready-to-use DMSO stock solutions, enabling fast labeling with bright signal and low background, while eliminating the extensive wash steps required by other haloalkane ligands.

Choose from 11 bright colors, with flexible options for intracellular or cell surface targets

ViaTag™ Haloalkane Ligand staining. Top row: HeLa cells were transiently transfected with NLS3-HaloTag® expression vector targeting HaloTag® to the cell nucleus. Transfected cells were fixed with PFA, then stained with ViaTag™ cell membrane-permeant ligands. Bottom row: PFA-fixed MCF7 cells stained with mouse anti-CD9 recombinant antibody (clone 2310.9) and anti-mouse SdAb-HaloTag® fusion, then stained with ViaTag™ cell membrane-impermeant ligands. Scale bars: 50 um.

Key Advantages of ViaTag™ Haloalkane Ligands:

• Rapid covalent labeling of HaloTag® self-labeling tags
• Stable and ready-to-use DMSO stock solutions
• No need for extensive wash steps
• Cell permeant and impermeant ligands for labeling intracellular or cell-surface targets
• Wide selection of fluorescent colors from UV to near-IR
• Cost-effective alternative to other haloalkane ligands

ViaTag™ Haloalkane Ligands expand Biotium’s portfolio of high-performance fluorescent labeling tools, offering researchers a more economical, efficient, and versatile solution for HaloTag®-based imaging and detection across diverse experimental workflows.

For more information about ViaTag™ Haloalkane Ligands, please visit the product page. Biotium also offers a wide selection of cellular stains for labeling membranes, nuclei, and other organelles in live or fixed cells. This includes NucSpot^® Live Cell Nuclear Stains and CellBrite^® Steady Membrane Staining Kits for long-term imaging of nuclei and membranes in live cells, respectively. Learn more about our unique cellular stains or view our cellular stains guides to view stains available for specific workflows or organisms.

HALOTAG is a registered trademark of the Promega Corporation.