Efficient immunoprecipitation & purification of Spot-tagged proteins

ChromoTek Spot-Trap is a high quality Spot-Tag® binding protein coupled to agarose beads or magnetic agarose beads. The Spot-tag binding protein, also termed anti-Spot-Tag nanobody or anti-Spot-Tag VHH, is derived from heavy chain antibodies.  The Spot-Trap is an affinity resin for fast and effective immunoprecipitation and affinity purification. It is optimized for biochemical analysis of Spot-tagged proteins and their interacting partners. The Spot-Trap is well-characterized and validated.

Use Spot-Trap for:

  • Immunoprecipitation (IP) / Co-IP
  • Immunoprecipitation (IP) / Co-IP for Mass spec analysis
  • Affinity purification
  • Enzyme activity measurements


Spot-Tag is an inert 12 amino acid peptide tag with the sequence PDRVRAVSHWSS. Please find more information about the Spot-Tag here.

Spot-Trap is a very low background affinity reagent

See benchmark of Spot-Trap Agarose and Magnetic Agarose with other suppliers’ capture tools. Immunoprecipitations were conducted from HEK293T cell lysates without Spot-Tag present and normalized for equal binding capacity. The IPs were done according to respective manufacturers’ protocols. It is apparent that Spot-Trap does not only lack heavy and light chain antibody contaminations but also unspecific binding. This makes Spot-Trap a superior affinity capture tool for single band purification of Spot-tagged proteins.

Try before you buy: Get a test sample of the Spot-Trap® - in return we just need you to send back your test results within 4 weeks.

Immunoprecipitation of Spot-tagged protein


  • NO heavy & light antibody chains
  • High binding affinity
  • Harsh washing conditions
  • Short incubation time of 30-60 minutes



Pulldown of Spot-tagged protein. Input (I), non-bound (FT) and bound (B) fractions were separated by SDS-PAGE followed by Coomassie staining and Western blotting. Western blot indicates high effectiveness of pull-down.

Affinity purification

  • High affinity
  • Purification of low abundant proteins
  • Low background, pure results
  • Native and non-native elution


Elution of affinty purified, Spot-tagged protein. Input (I), non-bound (FT) and eluted (E1, E2 and E3) fractions were separated by SDS-PAGE followed by Coomassie staining and Western blotting. Elutions with Spot-peptide. Western blot indicates effective elution.

Regeneration of Spot-Trap beads is possible. It is recommended, however, to re-use beads for the repeated purification of the same protein only to avoid cross-contamination.

Available matrices for Spot-Trap


Spot-binding protein coupled toagarose beadsmagnetic agarose beads
matrixagarosemagnetic agarose
particle size90µm40µm
binding capacity for a 30kDa protein (resin)1.4µg/µl
centrifuged up to 3000g3000g


In addition, we offer non-conjugated Spot-Tag binding protein (=Spot-Nanobody):

  • Spot-Label for Western blot (WB), uncoupled
For Spot-Tag cloning information and available Spot vectors click here.