iFluor(R) IRDye 800RS Maleimide

iFluor(R) IRDye 800RS is a near-infrared fluorescent dye engineered for nucleic acid labeling applications. It exhibits high water solubility but reduced salt tolerance compared to iFluor(R) IRDye 800 CW. The increased hydrophobicity of iFluor(R) IRDye 800RS enhances its performance in organic solvent-based reactions while maintaining sufficient aqueous solubility, making it particularly suitable for conjugation to thiol-modified oligonucleotides and nucleic acids. The maleimide-functionalized derivative of iFluor(R) IRDye 800RS undergoes rapid and selective Michael addition with thiol groups under physiological conditions, enabling stable covalent attachment to thiol-modified DNA and RNA. This conjugation strategy is widely utilized in fluorescence-based hybridization assays, molecular imaging, and diagnostic applications. Following conjugation, labeled nucleic acids can be purified via reverse-phase chromatography, yielding high-purity conjugates with minimal residual unreacted dye. The physicochemical properties of iFluor(R) IRDye 800RS provide a controlled balance between aqueous and organic solubility, optimizing its utility in diverse labeling strategies requiring near-infrared fluorescence. iFluor(R) IRDye 800RS, manufactured by AAT Bioquest, is structurally identical to IRDye 800RS (IRDye(R) is the trademark of LI-COR).