SNAP-tag® Substrates

Cellular Analysis

NEB offers a large selection of fluorescent labels (substrates) for SNAP-fusion proteins. SNAP-tag® substrates consist of a fluorophore conjugated to guanine or chloropyrimidine leaving groups via a benzyl linker. Substrates label the SNAP-tag® without the need for additional enzymes. Cell-permeable substrates (SNAP-Cell®) are suitable for both intracellular and cell-surface labeling, whereas non-cell-permeable substrates (SNAP-Surface®) are specific for fusion proteins expressed on the cell surface only.

SNAP-tag®, SNAP-Cell® and SNAP-Surface® are registered trademarks of New England Biolabs, Inc.

  1. Fluorescent Labeling of COS-7 Expressing SNAP-tag Fusion Proteins for Live Cell Imaging

    Watch as Chris Provost, of New England Biolabs, performs fluorescent imaging of live COS-7 cells expressing SNAP-tag® fusion proteins.

  2. SNAP-tag Overview Tutorial

    View an interactive tutorial explaining the mechanism of our SNAP-tag® technologies and reagents available for researchers wishing to study the function and localization of proteins in live or fixed cells.

Featured Products

    Publications related to SNAP-tag Substrates:

  1. Zelman-Femiak, M. et al. (2010). Covalent quantum dot receptor linkage via the acyl carrier protein for single-molecule tracking, internalization, and trafficking studies BioTechniques . 49, 2. PubMedID: 20701592
  2. Waichman S. et al. (2010). Functional Immobilization and Patterning of Proteins by an Enzymatic Transfer Reaction Anal. Chem. . 82, 1478-1485. PubMedID: 20092261
  3. Mosiewicz, K. A. et al. (2010). Phosphopantetheinyl Transferase-Catalyzed Formation of Bioactive Hydrogels for Tissue Engineering J. Am. Chem. Soc. . 132, 5972-5974. PubMedID: 20373804
  4. Neugart F. et al. (2009). Detection of ligand-induced CNTF receptor dimers in living cells by fluorescence cross correlation spectroscopy Biochim. Biophys. Acta.  . 1788, 1890-1900. PubMedID: 19482006
  5. Eggeling C. et al. (2009). Direct observation of the nanoscale dynamics of membrane lipids in a living cell Nature . 457, 1159-1163. PubMedID: 19098897
  6. Gralle M. et al. (2009). Neuroprotective secreted amyloid precursor protein acts by disrupting amyloid precursor protein dimers J. Biol. Chem. . 284, 15016-15025. PubMedID: 19336403
  7. Generosi J. et al. (2008). AMPA receptor imaging by infrared scanning near-field optical microscopy Physica Status Solidi C: Current Topics in Solid State Physics . 5, 2641-2644.
  8. Sunbul M. et al. (2008). Enzyme catalyzed site-specific protein labeling and cell imaging with quantum dots Chem. Comm. . 5927-5929. PubMedID: 19030541
  9. Generosi J. et al. (2008). Photobleaching-free infrared near-field microscopy localizes molecules in neurons J. App. Phys. . 104, 106102-1/3.
  10. Kropf M. et al. (2008). Subunit-specific surface mobility of differentially labeled AMPA receptor subunits Eur. J. Cell Biol. . 87, 763-778. PubMedID: 18547676
  11. Zhou Z. et al. (2007). Genetically encoded short peptide tags for orthogonal protein labeling by Sfp and AcpS phosphopantetheinyl transferases ACS Chemical Biology . 2, 337-346. PubMedID: 17465518
  12. Liu E and Bruner S. D. (2007). Rational manipulation of carrier-domain geometry in nonribosomal peptide synthetases ChemBioChem. . 8, 617 - 621. PubMedID: 17335097
  13. Meyer B.H. et al. (2006). Covalent labeling of cell-surface proteins for in vivo FRET studies FEBS Letters . 580, 1654-1658. PubMedID: 16497304
  14. Meyer B.H. et al. (2006). FRET imaging reveals that functional neurokinin-1 receptors are monomeric and reside in membrane microdomains of live cells Proc. Natl. Acad. Sci. USA . 103, 2138-43. PubMedID: 16461466
  15. Prummer M. et al. (2006). Post-translational covalent labeling reveals heterogeneous mobility of individual G protein-coupled receptors in living cells ChemBioChem . 7, 908-911. PubMedID: 16607667
  16. Jacquier V. et al. (2006). Visualizing receptor trafficking in living PNAS . 103, 14325-14330. PubMedID: 16980412
  17. Yin J. et al. (2005). Labeling proteins with small molecules by site-specific posttranslational modification J Am Chem Soc. 126, 7754-7755. PubMedID: 15212504
  18. Cravatt B.F. (2005). Live chemical reports from the cell surface Chem. Biol. . 12, 954-956. PubMedID: 16183017
  19. Vivero-Pol L. et al. (2005). Multicolor imaging of cell surface proteins J. Am. Chem. Soc. . 127, 12770-12771. PubMedID: 16159249
  20. Yin J. et al. (2005). Single-cell FRET imaging of transferrin receptor trafficking dynamics by Sfp-catalyzed, site-specific protein labeling Chem. Biol . 12, 999-1006. PubMedID: 16183024
  21. La Clair, J.J. et al. (2004). Manipulation of carrier proteins in antibiotic biosynthesis Chem. Biol. . 11, 195-201. PubMedID: 15123281
  22. George N. et al. (2004). Specific labeling of cell surface proteins with chemically diverse compounds J .Am. Chem. Soc.  . 126, 8896-8897. PubMedID: 15264811


  • Naturally Secreted – Used in live cell assays
  • Sensitivity – Brightest luciferases available; enables single cell applications 
  • Stability – Samples can be stored for several days with no loss of activity 
  • Easy-to-use – Cell lysis not necessary 
  • Non-destructive – Living cells can be used in downstream assays 
  • Flexible – Activity can also be measured in cell lysates


  • Transfection optimization studies 
  • Promoter/enhancer assays 
  • High throughput assays 
  • Multiplex assays 
  • Multiple assays with other reporters
  • Secretory pathway reporter assays
  • Signal transduction
  • siRNA potency screening
  • Time course studies
  • Single cell assays, including stem cells and primary cells
  • Live cell assays
  • Assays in difficult to transfect cells

NEB vs Other Commercially Available Reporter Systems

Features Gaussia Cypridina Renilla Firefly Metridia
Extreme Sensitivity      
Does not require and is
not affected by ATP

Comparison of the features of commercially available reporter systems highlights the advantages of using Gaussia or Cypridina Luciferase from NEB.

Reporter System Selection Chart

NEB offer a variety of products that utilize secreted Gaussia Luciferase (GLuc) and Cypridina Luciferase (CLuc) in reporter assays.