FSD EX Fluor™ 800 NHS Ester is a next-generation, amine-reactive NIR fluorescent dye developed through BioActs’ advanced technology. It offers excellent optical performance and strong brightness compared with spectrally similar dyes, making it suitable for high-sensitivity analytical applications. FSD EX Fluor™ 800 exhibits excitation and emission maxima (Ex/Em = 777/792 nm) comparable to IRDye 800, Cy7.5, and CF770. The dye can be efficiently excited by 750 or 785 nm laser lines, emitting within the NIR region that allows deep-tissue penetration and reduced background interference. It provides high brightness and photostability ideal for long-term and live imaging. The NHS ester form reacts with amine-modified oligonucleotides or primary amines to form stable amide linkages, enabling efficient conjugation and stable fluorescence even with low-abundance targets. FSD EX Fluor™ 800 NHS Ester is optimized for in vivo NIR fluorescence imaging and detection applications.

Special Properties (NIR Characteristics)

FSD EX Fluor™ 680, 750, and 800 dyes emit within the near-infrared region (NIR-I, 650–900 nm), known as the optical window of biological tissues. In this spectral range, absorption and scattering by biomolecules such as hemoglobin, water, and lipids are minimal, allowing deep tissue penetration and low background autofluorescence. These dyes provide high signal-to-noise ratios and excellent photostability, making them ideal for in vivo and deep-tissue fluorescence imaging.