The Buccutite™ Rapid PE-iFluor® 594 Tandem Antibody Labeling Kit provides a streamlined approach for efficient, small-scale labeling of antibodies with PE-iFluor® 594. Compared to conventional methods such as SMCC crosslinking, Buccutite™ technology offers a more straightforward and reproducible solution. Using a simple two-step mixing protocol, antibodies or proteins can be conjugated with PE-iFluor® 594 in less than two hours. Each kit includes all reagents necessary for two labeling reactions, with Buccutite™ FOL-Activated PE-iFluor® 594 vials specifically formulated to label 100 µg of purified protein or antibody per reaction. Prior to labeling, stabilizing proteins (e.g., BSA) should be removed, and amine-rich buffers such as Tris should be avoided to prevent interference with the labeling chemistry. PE-iFluor® 594 is a tandem fluorophore with excitation and emission maxima at ~565 nm and ~606 nm, respectively. Its high fluorescence intensity makes it particularly suitable for detecting low-abundance targets while minimizing spectral spillover and reducing compensation complexity. These properties make PE-iFluor® 594 an excellent choice for flow cytometry, spectral flow cytometry, and other immunoassays requiring high sensitivity. However, it is not recommended for applications where photostability is critical. This kit enables direct conjugation of primary antibodies, eliminating the need for secondary antibody labeling strategies. The resulting conjugates streamline workflows and facilitate the development of complex multicolor assays, enhancing experimental flexibility and reducing reagent complexity.