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Halo-Trap Agarose

Halo-Trap Agarose are affinity beads for immunoprecipitation of Halo-tag fusion proteins. It comprises a Halo-tag Nanobody /VHH conjugated to agarose beads.


Immunoprecipitation/ Co-IP
Mass spectrometry
On-bead enzyme assays
ChIP/ RIP analysis

Product Size Code Price Buy
Product Halo-Trap Agarose Size 250 µL (10 reactions) Code ota-10 Price $ 275
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Product Halo-Trap Agarose Size 500 µL (20 reactions) Code ota-20 Price $ 475
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Product Halo-Trap Agarose Size 2.5 mL (100 reactions) Code ota-100 Price $ 2050
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Product Halo-Trap Agarose Size 5 mL (200 reactions) Code ota-200 Price Please inquire
Product Halo-Trap Agarose Size 10 mL (400 reactions) Code ota-400 Price Please inquire
Product Halo-Trap Agarose Kit Size 500 µL (20 reactions) Code otak-20 Price $ 595
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Product Binding Control Agarose Beads Size 500 µL (20 reactions) Code bab-20 Price $ 75
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Product Spin Columns Size 10 units Code sct-10 Price $ 35
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Product Spin Columns Size 20 units Code sct-20 Price $ 60
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Product Spin Columns Size 50 units Code sct-50 Price $ 130
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Product Halo VHH, recombinant binding protein Size 250 µL Code ot-250 Price $ 365
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Dissociation constant KD of 2 nM

Wash buffer compatibility
4 M urea, 1 M NaCl, 10 mM DTT,  2 % Nonidet P40 Substitute, 1 % Triton X-100


Coupled Nanobody/ VHH
Recombinant, monoclonal anti-Halo single domain antibody (sdAb) fragment

Bead properties
Bead size: ~ 90 µm (cross-linked 4 % agarose beads)
Storage buffer: 20 % EtOH

- SDS sample buffer
- 0.1 mM citric acid pH 3.0
Instead of elution, we recommend on-bead assays like on-bead digestion for MS analysis.

Compatibility with mass spectrometry
The Halo-Trap is optimized for on-bead digestion. Complete tryptic digest results in 6-7 peptides.

Storage instructions
Shipped at ambient temperature. Upon receipt store at 4°C. Stable for one year.

How to cite this product

Should I use an N-terminal or C-terminal fusion tag?

Both the N-terminal or C-terminal fusion tag work well with the traps.

How can I avoid unspecific protein interactions binding to the trap?

For preclearing of your sample we recommend to use our binding controls (bab-20 or bmab-20).

Please find more information in our Troubleshooting guide

How can I elute bound proteins from a trap in their native state?

You can elute your fusion protein of interest with 0.2 M glycine pH 2.5 at room temperature. Pipette the beads up and down for 60-120 seconds and repeat this step. Ensure to neutralize your supernatant immediately afterwards by adding 1 M Tris base pH 10.4.

How many mammalian cells are required for an immunoprecipitation reaction?

For one immunoprecipitation reaction, we recommend using ~10^6 - 10^7 mammalian cells. The yield is also dependent on the expression level of your protein of interest and the interaction partners.

How much cell extract should I use for an immunoprecipitation reaction?

For other type of cells than mammalian cells, we recommend using 0.5 - 1.0 mg of cell extract.

Do I need to elute bound proteins from the beads for mass spectrometry analysis?

No, you can directly conduct an on-bead digestion after immunoprecipitation. This procedure allows faster and more efficient sample preparation and a potential higher yield.
Please find more information here:

Preomics kit

Protocol on-bead digestion

Do I need to elute my protein of interest from the beads for enzymatic assays?

No, you can directly perform your enzymatic assay on the beads if the active center is not blocked.

Please find more information in our application note "enzymatic activity assay"

What is the amount of trap slurry I need for one immunoprecipitation reaction?

25 µL slurry are sufficient for one pull-down reaction as the affinity of the traps is very high.

Specifications of Halo-Trap Agarose, Magnetic Agarose, and Magnetic Beads





Magnetic Agarose

Magnetic Particles M-270


Agarose (4% cross-linked)

Magnetic agarose (6% cross linked)

Magnetic Particles M-270

Bead form


Porous; sold iron core



Halo VHH

Halo VHH

Halo VHH

Halo-tagged protein size*

Small to large size

Small to large size

Small to very large size; no size limitation





Medium particle size

90 µm

40 µm

2.8 µm

Binding capacity

9 µg/ 10 µL

8 µg/ 10 µL

0.5 μg/ 10 μL


Very low



Magnetic separation & automation




May be centrifuged up to

2,500 x g

800 x g

8,000 x g

* Does depend on protein size and shape, protein multimers, complexes and interaction partners


  • Halo Trap recognizes Halo fusion proteins that are already bound to chloralkane-based ligands of the Halo-tag, e.g. dyes, biotin, etc.
  • Halo-Trap can be used for affinity purification
  • Bound Halo-fusion protein can be eluted without protease
  • Structure and function are characterized

Halo-Trap Agarose Kit

The Halo-Trap Agarose is also available in a kit, including:

  • Halo-Trap Agarose
  • lysis*, wash and elution buffers

*The lysis buffer provided is suitable for mammalian cells. For other cell types use another suitable lysis buffer.

Spin Columns

  • Easy and convenient handling
  • Rapid washing and clean elution of bound proteins
  • Simplify the pulldown of your protein
  • Spin Columns for Halo-Trap_Agarose

Binding Control for Agarose Beads

  • Control for unspecific binding of proteins, DNA, etc. to beads
  • Pre-clearing of cell lysate
  • Binding Control for Halo-Trap Agarose

Which Halo-Trap should I use?

•    Halo-Trap Agarose, when lowest background and high binding capacity IP is needed. 
•    Halo-Trap Magnetic Agarose, when magnetic separation and high binding capacity IP is needed.
•    Halo-Trap Magnetic Particles M-270, when very large proteins/complexes are investigated, and magnetic separation is needed for IP.

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Only for research applications, not for diagnostic or therapeutic use!