Cy5 DBCO | CAS 2182601-72-3

Cy5 DBCO is a fluorescent DBCO (dibenzocyclooctyne) click chemistry reagent that combines a near-infrared Cyanine 5 dye with a strained cyclooctyne for copper-free strain-promoted azide–alkyne cycloaddition (SPAAC). Its dye-labeled DBCO scaffold is designed to react selectively with azide-functional biomolecules, polymers, and surfaces under mild conditions, making it a widely used tool for labeling, tracking, and imaging workflows. Because Cy5 provides strong optical contrast and DBCO enables rapid bioorthogonal conjugation, Cy5 DBCO is commonly incorporated into research protocols for fluorescent bioconjugates and click-derived materials.

1. Live-Cell Imaging Conjugates

Cy5 DBCO is used to generate fluorescent azide-tagged conjugates for microscopy and imaging experiments, where researchers need a stable near-infrared signal and a copper-free labeling strategy compatible with sensitive biological samples. The reagent is particularly valuable when azide handles are introduced onto proteins, peptides, glycans, or other targeting ligands, enabling rapid formation of Cy5-labeled products that can be visualized by fluorescence imaging. In typical workflows, Cy5 DBCO serves as a labeling reagent for click-modified biomolecules prepared upstream, supporting downstream visualization, colocalization studies, and assay development that benefits from SPAAC’s fast, selective conjugation.

2. Protein and Antibody Labeling

Cy5 DBCO is frequently applied to fluorescently tag azide-functional proteins and antibody derivatives for binding studies, reagent characterization, and multiplex labeling strategies. Many laboratories install azide groups onto antibodies, antibody fragments, or protein scaffolds and then use Cy5 DBCO to install the Cy5 fluorophore through SPAAC, producing well-defined fluorescent conjugates for analytical and imaging readouts. The DBCO functionality is well suited for workflows that prioritize gentle conjugation conditions and straightforward post-functionalization, allowing researchers to compare labeling densities, track conjugate stability, and prepare imaging reagents for experimental platforms that rely on optical detection.

3. Biomaterials Surface Functionalization

Cy5 DBCO is used to fluorescently visualize and quantify azide-functionalized biomaterial surfaces, hydrogels, and polymer coatings, supporting studies that require spatially resolved labeling of engineered matrices. Researchers often incorporate azide groups into material backbones or surface chemistries and then apply Cy5 DBCO to introduce fluorescent reporters via click conjugation, enabling assessment of coating uniformity, surface accessibility, and material patterning. This application is common in biomaterials science where near-infrared fluorescence is leveraged to monitor functionalization outcomes and to track the distribution of clickable components within complex material architectures.

4. Molecular Imaging Probe Development

Cy5 DBCO is a practical building block for constructing Cy5-based imaging probes and fluorescent reporters from azide-bearing targeting vectors, including small molecules, linkers, and scaffolded ligands used in molecular imaging research. By using SPAAC to attach Cy5 to azide handles, probe developers can rapidly generate libraries of fluorescent conjugates with consistent dye presentation and convenient downstream handling. The Cy5 DBCO reagent is often integrated into iterative design cycles where azide-functional probe candidates are prepared and then labeled with Cy5 DBCO to enable optical readouts such as fluorescence-guided localization, imaging contrast optimization, and probe characterization in research settings.