iFluor(TM) 532 succinimidyl ester

Molecular weight: 914.06 Excitation (nm): 537, Emission (nm): 560, Absorbance (nm): 536, Extinction coefficient (cm-1 M-1): 90000, Quantum yield: 0.68. AAT Bioquest's iFluor(TM) dyes are optimized for labeling proteins, in particular, antibodies. These dyes are bright, photostable and have minimal quenching on proteins. They can be well excited by the major laser lines of fluorescence instruments (e.g., 350, 405, 488, 555 and 633 nm). iFluor(TM) 532 dyes have fluorescence excitation and emission maxima of ~532 nm and ~553 nm respectively. These spectral characteristics make them an excellent upgrade to Alexa Fluor(R) 532 labeling dye (Alexa Fluor(R) is the trademark of Invitrogen). iFluor(TM) 532 is perfectly excited at 532 nm with its maximum excitation at 531 nm while Alexa Fluor(R) 532 has its maximum excitation at 524 nm (~8 nm off the desired 532 nm laser line). iFluor(TM) 532 has its fluorescence quantum yield higher than Alexa Fluor(R) 532 by ~40% under the same conditions. In addition, iFluor(TM) 532 is much more stable at high pH range (e.g., 8-10, commonly used in DNA sequencing) than Alexa Fluor(R) 532. iFluor(TM) 532 SE is reasonably stable and shows good reactivity and selectivity with protein amino groups.