Tetrafluorophenyl (TFP) esters are an improvement over the succinimidyl ester (SE or NHS-ester) chemistry typically used to attach fluorophores or haptens to the primary amines of biomolecules. Both reactive chemistries produce the same strong amide bond between the dye or hapten and the compound of interest, but TFP esters are less susceptible to spontaneous hydrolysis during conjugation reactions. Alexa Fluor TFP esters are stable for several hours at the basic pH typically used for reactions – far outlasting succinimidyl esters.
Size: 1 mg
The amine-reactive Alexa Fluor 430 carboxylic acid, succinimidyl ester and its conjugates exhibit the rare combination of absorption between 400 nm and 450 nm and fluorescence emission beyond 500 nm (excitation/emission maxima ~434/539 nm).
Size: 5 mg
This single 5-isomer preparation of our proprietary, amine-reactive dye, Oregon Green 488 carboxylic acid, succinimidyl ester and its conjugates have green fluorescence similar to that of fluorescein but are more photostable. Additionally, Oregon Green 488 dye has a lower pK a than fluorescein (pK a = 4.7 versus 6.4 for fluorescein), making this bright dye less pH sensitive in the physiological range.
Size: 5 mg
To permit simultaneous long-term tracing of mixed-cell populations using different fluorescent colors, we have developed a probe whose applications should be similar to those of CFDA SE (commonly called CFSE). Cells labeled with our SNARF-1 carboxylic acid, acetate, succinimidyl ester have orange-red fluorescence that can be easily distinguished from that of cells loaded with green-fluorescent tracers such as CFDA SE.
Size: 10 x 50 µg