Cy5 Tetrazine

Unit Size
Price (USD)
1 mg
In stock
5 mg
In stock
25 mg
In stock

Tetrazines demonstrate exceptionally fast cycloaddition kinetics (up to 30 000 M-1 s-1) with trans-cyclooctenes (TCO) as the dienophile, the fastest kinetics ever reported for any bioorthogonal reaction. In addition, inverse-Electron-Demand Diels-Alder reaction of tetrazines trans-cyclooctenea forms a stable covalent bond and does not require Cu-catalyst or elevated temperatures. In applications such as in vivo cancer imaging or pre‐targeted cell labeling studies where rapid reaction kinetics is a must, a faster hydrogen substituted Cy®5 Tetrazine probe would be a probe of choice.

Abs/Em Maxima
649/670 nm
Extinction Coefficient
Flow Cytometry Laser Line
633 or 635 nm
Microscopy Laser Line
633 or 635 nm
Spectrally Similar Dyes
Alexa Fluor® 647, Atto™ 647, CF™ 647 Dye, DyLight™649
Molecular weight
Water, DMSO, DMF
>95% (HPLC)
Blue solid
Storage conditions
-20°C. Desiccate
Shipping conditions
Ambient temperature

Terazine-activated Cy5 dye reacts with TCO-containing compounds via a Inverse-Electron-Demand Diels-Alder reaction to form a stable covalent bond and does not require Cu-catalyst or elevated temperatures. The inverse-electron demand Diels-Alder cycloaddition reaction of TCO with tetrazines is a bioorthogonal reaction that possesses exceptional kinetics and selectivity. Such excellent reaction rate constants are unparalleled by any other bioorthogonal reaction pair described to date.

Cy5 Tetrazine is a water-soluble, pH-insensitive from pH 4 to pH 10, far-red-fluorescent probe with excitation ideally suited for the 633 nm or 647 nm laser lines. Its absorption and emission spactra are almost identical to those of Alexa Fluor® 647, CF® 647 Dye, or any other Cyanine5 based fluorescent dyes.

This is sulfonated dye is also known as sulfo-Cyanine5.

Cy®Dye is a trademark of GE Healthcare. Alexa Fluor® is a registered trademark of Thermo Fisher Scientific. CF® Dye is a registered trademark of Biotium, Inc


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