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The ChromoTek RFP-Trap® is a ready to use affinity resin for immunoprecipitation (IP) of red fluorescent-fusion proteins like mCherry, dsRed, mRFP, and more.

RFP-Trap consists of an anti-RFP Nanobody/ VHH coupled to agarose beads, magnetic agarose beads or solid magnetic particles. ChromoTek’s RFP-Trap is referenced in about 300 scientific articles.

mCherry, mRFP, mRFPruby, mPlum, tagRFP, mKate2 and many more RFP derivatives, see:
Fluorescent protein specificity table

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

RFP-Trap Agarose
RFP-Trap Magnetic Agarose
RFP-Trap Magnetic Particles M-270
RFP VHH, recombinant binding protein
iST RFP-Trap Kit for IP plus sample preparation for MS

anti-RFP VHH, RFP binding protein, RFP Nanobody, or anti-RFP single domain antibody fragment (sdAb)

Benefit from RFP-Trap for Immunoprecipitation (IP)

  • Reliable and robust pull-down of mCherry and other RFP-fusion proteins
  • From cell to gel in less than one hour
  • High affinity
  • Strong binding even under harsh washing conditions
  • No heavy & light chains in your downstream application

What RFP-Trap shall I use?

  • RFP-Trap Agarose, when lowest background and high binding capacity IP is needed. 
  • RFP-Trap Magnetic Agarose, when magnetic separation and high binding capacity IP is needed.
  • RFP-Trap Magnetic Particles M-270, when very large proteins/complexes are investigated, and magnetic separation is needed for IP.
  • iST RFP-Trap kit for immunoprecipitation plus sample preparation for mass spectrometry (MS)

Comparison of matrices & properties

We offer RFP-Trap as Agarose, Magnetic Agarose, and Magnetic Particles M-270.

  RFP-Trap Agarose  RFP-Trap Magnetic Agarose  RFP-Trap Magnetic Particles M-270
Low background  +++  ++  ++
Binding capacity  +++  +++  +
Size RFP-tagged protein*   Small to large  Small to large  Small to very large
Bead separation  Centrifugation  Magnetic  Magnetic

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

Extraordinary stable & reliable binding

  • Dissociation constant KD of 5 nM
  • Compatible to harsh wash conditions: 4 M urea, 2 M NaCl, 10 mM DTT, 2 % Nonidet P40 Substitute, 1 % Triton X-100 (RFP-Trap Magnetic Beads: 10mM DTT, 500 mM NaCl, 2 % Nonidet P40 Substitute, 2 % Triton X-100)
  • Fully applications validated and characterized


The RFP-Trap specifically binds to

  • mCherry, mOrange
  • mRFP, mRFPruby, mPlum, tagRFP, mKate2, mScarlet

See full fluorescent protein specificity list here.

About RFP

The first red fluorescent protein (RFP) that became commercially available is DsRed. It was isolated from Discosoma sp in 1999. Additional RFPs have been isolated from Anthozoa. Site directed mutagenesis was used to create RFP derivatives with fluorescence in orange, red, and far red colors. Also, monomerized versions were generated and brightness, maturation efficiency, and photostability were improved, making theses RFPs valuable research tools.



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