Atto 700 (Figure 1) is a far-red fluorescent dye with high brightness, strong absorption, and excellent photostability. It is well suited for demanding applications such as single-molecule detection, flow cytometry (FACS), and fluorescence in-situ hybridization (FISH), where stable and sensitive signal detection is required.
The dye is zwitterionic, becoming electrically neutral after conjugation to a substrate, which helps reduce nonspecific interactions. Atto 700 shows strong electron-accepting behaviour, and its fluorescence can be influenced by nearby electron-rich residues such as guanine or tryptophan.
It is efficiently excited in the 680–710 nm range, typically using diode lasers around 690–700 nm, making it compatible with modern far-red detection systems.
Atto 700 can be used as an alternative to Alexa Fluor® 700.
Figure 1. Structure of 5'-Atto 700 (R = sequence)
metabion offers Atto 700 as part of its Dual-Labelled Probe Portfolio.