SiR650-BG Substrate

SiR650-BG is the benzylguanine derivative of our SiR fluorophore. It emits light in the far-red, it is fluorogenic, highly cell permeable and well suited for STED and SIM superresolution imaging. SiR650-BG can be imaged with a standard Cy5 filterset. It can be used for widefield, confocal, SIM or STED imaging in living or fixed cells and tissue. It has the same structure as SNAP-Cell® 647-SiR and also identical to SiR-SNAP, the name used in its original publication in Nature Chemistry.
Benzylguanine (BG) is the substrate of the self labeling tag SNAP-tag™*. Upon reaction with a BG derivative, SNAP-tag™* forms a covalent bond with the substrate and releases guanine. It allows to permanently attach a fluorescent label to any protein of interest (POI) expressed as SNAP-tag™* fusion.

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

Absorbance maximum λabs: 652 nm
Fluorescence maximum λfl: 674 nm
Works on fixed cells? yes, PFA and methanol
Probe quantity: 35 nmoles
Fluorescence lifetime: 3.0 ns
STED depletion wavelength: 775 nm
Shipping: room temperature
Storage: -20°C

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