IRDye® 680LT Carboxylate | CAS 1236312-58-5

IRDye® 680LT Carboxylate is a near-infrared fluorescent dye designed for covalent attachment to biomolecules and materials via its carboxylate functionality. The long-wavelength emission supports low-background fluorescence workflows in microscopy, imaging, and quantitative fluorescence assays, where NIR detection is advantageous for reducing interference from autofluorescence. In research settings, it is commonly used to generate fluorescent conjugates for labeling, tracking, and assay readouts.

1. Fluorescent Antibody Labeling

IRDye® 680LT Carboxylate is widely used by immunochemistry and assay development teams to prepare NIR fluorescent antibody conjugates for binding and detection workflows. Researchers typically couple the dye to lysine-containing antibodies or antibody fragments to create imaging reagents that can be read on NIR-capable fluorescence imaging systems or plate-based fluorescence readers. This labeling approach is frequently applied in Western blot-style fluorescence detection, immunodetection assays, and quantitative binding studies where NIR emission helps suppress background from biological samples and membranes.

2. Protein and Peptide Tracing

IRDye® 680LT Carboxylate supports fluorescent labeling of proteins and peptides for molecular tracking in biochemical and biomaterials research. Investigators use dye-conjugated biomolecules to follow transport, binding, or retention in solution-based assays and surface-associated experiments, including studies of adsorption to polymers, nanoparticles, or engineered surfaces. The carboxylate handle enables preparation of stable fluorescent conjugates that are compatible with common NIR imaging and fluorescence quantification workflows used in chemistry, chemical biology, and materials characterization.

3. NIR Fluorescence Imaging Assays

IRDye® 680LT Carboxylate is used to build quantitative NIR fluorescence readouts for imaging-based assay development, including endpoint fluorescence measurements in microplate formats and fluorescence imaging in small-scale sample studies. Researchers select this dye when they want NIR signal collection to reduce autofluorescence contributions from complex matrices such as cell lysates, culture media components, or polymeric materials. Dye-labeled targeting reagents and reference conjugates prepared from IRDye® 680LT Carboxylate are commonly incorporated into assay calibration, normalization controls, and comparative studies across experimental conditions.

4. Biomaterial Surface Functionalization

IRDye® 680LT Carboxylate is employed in biomaterials science to introduce NIR fluorescence into functionalized surfaces and coatings for characterization and imaging. Lab groups use dye-functionalized materials to visualize surface coverage, monitor coating uniformity, and track biomolecule immobilization on substrates such as polymer films, hydrogels, or nanoparticle surfaces. The dye's covalent labeling capability helps generate stable fluorescent tags that can be imaged using NIR fluorescence instrumentation to support materials development and process monitoring in research and industrial R&D environments.