Invitrogen Corp. (Carlsbad, CA) offers a new color for its Molecular Probes Qdot fluorescent label product lines. Qdot 625 nanocrystal fluorescent label can be seen as orange and fills an important spectral gap or dense multi-color experiments. Current products using the Qdot 625 nanocrystal include the Qdot 625 streptavidin conjugate, the Qdot 625 goat F(ab')2 anti-mouse IgG conjugate and the Qdot 625 F(ab')2 anti-rabbit IgG conjugate. When excited by a single light source, Qdot nanocrystals emit in a range of brilliant colors with long-term photostability, offering researchers flexibility when designing multi-color flow cytometry panels.