Blocking Agents

Cellular Analysis
  • My NEB
  • Print
  • PDF
  • Blocking agents are non-fluorescent compounds that block the reactivity of the SNAP- or CLIP-tag intracellularly (SNAP-Cell® Block, NEB #S9106; and CLIP-Cell™ Block, NEB #S9220) or on the surface of live cells (SNAP-Surface® Block, NEB #S9143; and CLIP-Cell Block). They can be used to generate inactive controls in live cell labeling experiments performed with SNAP- or CLIP-tag fusion proteins. 

    SNAP- and CLIP-Cell Block are highly membrane permeable and once in the cell react with the SNAP- or CLIP-tag, irreversibly inactivating it for subsequent labeling steps. 

    SNAP-Surface Block also reacts with the SNAP-tag irreversibly, inactivating it for subsequent labeling steps. This blocker is largely membrane impermeable essentially limiting blocking to cell surface-exposed SNAP-tags. CLIP-Cell Block may also be used to inactivate cell supface exposed CLIP-tags.

    SNAP-Cell® and SNAP-Surface® are registered trademarks of New England Biolabs, Inc.
    CLIP-Cell is a trademark of New England Biolabs, Inc.

    Featured Products

      Other Tools & Resources


    • Cellular Imaging and Analysis Brochure

      The Cellular Imaging and Analysis brochure provides information on the labeling technologies offered by NEB for studying the function and localization of proteins in cells.

    Blocking Agents Selection Chart