DBCO-C6-NHS ester | CAS 1384870-47-6

DBCO-C6-NHS ester is a cyclooctyne (DBCO)-functionalized NHS ester designed for copper-free click chemistry conjugation with azide-bearing partners. The reagent couples the NHS-activated ester chemistry to amine-containing surfaces and biomolecules, while the DBCO handle enables rapid strain-promoted azide–alkyne cycloaddition (SPAAC) in aqueous conditions. Its modular C6 linker and NHS reactivity make it widely used for preparing azide-reactive labeling kits, bioconjugation intermediates, and functional biomaterials that can be further decorated with azide tags.

1. Protein And Peptide Labeling

DBCO-C6-NHS ester is commonly used to functionalize proteins, peptides, and protein-derived reagents via NHS ester acylation of primary amines. This approach is frequently selected when researchers need a stable DBCO-bearing bioconjugate that can later undergo copper-free ligation to azide-functional probes, including fluorescent reporters, affinity tags, or biomolecular handles for downstream assays. The C6 spacer helps maintain accessibility of the DBCO group, which is particularly useful when labeling folded proteins or multivalent peptide constructs where steric effects can limit click efficiency.

2. Antibody And Targeting Conjugates

DBCO-C6-NHS ester supports DBCO installation onto antibodies and antibody fragments through amine-reactive NHS chemistry, enabling subsequent azide-directed conjugation to imaging reagents or targeting modules. Many molecular imaging and chemical biology workflows use this reagent to generate antibody–probe conjugates with defined click handles, allowing modular assembly of conjugates from separately prepared azide-labeled components. This strategy is also used to create dual-functional targeting constructs, such as antibodies linked to azide-bearing nanoparticles or azide-tagged affinity ligands, where orthogonal assembly is preferred over direct chemical coupling.

3. Surface and Material Functionalization

DBCO-C6-NHS ester is widely applied to functionalize solid supports and biomaterials that present accessible amines, including polymer surfaces, hydrogel matrices, and amine-derivatized beads. By anchoring DBCO groups onto the material through NHS ester chemistry, researchers can create clickable interfaces for subsequent immobilization of azide-functional biomolecules, including enzymes, binding proteins, or fluorescent standards. This material-first workflow is valuable in assay development and molecular diagnostics reagent engineering, where stable, spatially controlled presentation of clickable ligands improves reproducibility and allows streamlined batch preparation of azide-reactive surfaces.

4. Multicolor Imaging Probe Assembly

DBCO-C6-NHS ester is frequently used as a DBCO-priming reagent to generate azide-reactive labeling partners for multicolor imaging and multiplexed chemical biology experiments. In these workflows, the NHS ester step installs DBCO onto an amine-containing scaffold such as a protein conjugate, polymer carrier, or nanoparticle surface, and the resulting DBCO conjugate is later reacted with azide-bearing dyes or imaging moieties using copper-free click chemistry. The modular nature of this two-step assembly supports flexible probe swapping, enabling researchers to build imaging panels with consistent chemistry and handle compatibility across different targets and labeling formats.