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.