iFluor® 625 succinimidyl ester is the most convenient reactive form of iFluor® 625 dyes that can be readily used for labeling proteins such as antibodies. It is particularly useful for preparing PE tandems, a new unique color for multiplex flow cytometric applications. iFluor®625 is a fluorophore from the iFluor® family, which is known for its bright red fluorescence and compatibility with various fluorescence techniques and instruments. When excited with light in the red range (around 600 to 650 nm), iFluor® 625 emits strong red fluorescence. It can also be well excited with red lasers at 633 and 647 nm. iFluor® 625 can be conjugated to a variety of biomolecules, including antibodies, proteins, nucleic acids, and small molecules, enabling their visualization and tracking in cells and tissues. It is commonly used in fluorescence microscopy, immunohistochemistry, flow cytometry, and other fluorescence-based assays. The iFluor® dyes, including iFluor® 625, are designed to exhibit high brightness, photostability, and minimal background noise, making them ideal for demanding imaging applications. They are also compatible with multiplexing experiments, allowing for simultaneous visualization of multiple targets using different iFluor® dyes with distinct emission wavelengths.