Product Name: Square-650-pH-NHS

Description

• pH-sensitive, fluorescent label containing one reactive NHS-ester group and pKa in the physiological pH range (pKa = 7.1 - free dye, pKa ~ 6.3 when labeled to antibody).

Applications

• Cell-based imaging applications (ratiometric or FLIM) of e.g. receptor translocations, plasma membrane-associated receptor activation, or GPCR-ligand interactions via endocytosis.
• Covalent labeling of proteins, amino-modified DNA and amino-modified oligonucleotides, and amino-modified lipids.

Advantages

• The protonated form of this dye is excitable with orange and red light sources and is perfectly suited for excitation with 594-nm, 635-nm, and 650-nm LEDs and diode lasers, while the deprotonated form is excitable with green and orange light sources and is suited for excitation with 532-nm, 550-nm, and 594-nm LEDs and diode lasers. The absorbance of both protonated and deprotonated forms is equal at 589 nm.
• Sensitive; high extinction coefficients and high quantum yields up to 16% after covalent attachment to biomolecules.
• pH-label that exhibits intensity as well as lifetime-based changes with pH.
• Good aqueous solubility; this label does not alter the solubility of the conjugate.
• Ideal for non-radioactive labeling of proteins, amino-modified DNA probes, and amino-modified oligonucleotides.