DBCO-PEG4-amine | CAS 1840886-10-3

DBCO-PEG4-amine is a difluorinated cyclooctyne (DBCO)-based click chemistry reagent bearing a PEG4 spacer and a terminal primary amine. As a strain-promoted azide–alkyne cycloaddition (SPAAC) handle, it is widely used to install DBCO functionality onto azide-bearing biomolecules, surfaces, and materials without requiring copper catalysis. The PEG4 linker provides aqueous compatibility and spacing that can improve conjugation accessibility, while the amine enables subsequent coupling to activated esters, aldehydes, or other NHS-reactive chemistries for downstream assembly of probes, coatings, and functional biomaterials.

1. Antibody And Protein Conjugation

DBCO-PEG4-amine is commonly used in click-enabled labeling workflows for antibodies and other proteins where a stable, copper-free SPAAC reaction is preferred. The terminal amine supports attachment to NHS-activated dyes, carboxylate-activated linkers, or other amine-reactive scaffolds, enabling modular construction of imaging reagents and affinity reagents. Researchers often incorporate the PEG4 spacer to reduce steric hindrance and maintain binding performance during multistep conjugation, particularly when preparing azide-functional protein targets for subsequent DBCO-driven coupling.

2. Surface And Material Functionalization

DBCO-PEG4-amine is frequently applied to functionalize polymers, nanoparticles, and biomaterial surfaces that are engineered with azide groups for later click coupling. The PEG4 chain improves dispersion and reduces nonspecific interactions when immobilizing DBCO-containing layers on hydrophilic substrates, while the primary amine provides a versatile anchoring point for attachment to activated surfaces or for crosslinker-mediated incorporation into coatings. This makes DBCO-PEG4-amine a practical building block for creating spatially controlled, click-reactive interfaces used in materials research and assay development.

3. Fluorescent And Imaging Probe Assembly

DBCO-PEG4-amine supports the construction of fluorescent and molecular imaging probes through sequential conjugation strategies that combine amine-reactive labeling with azide–DBCO SPAAC coupling. The reagent’s PEG4 spacer helps optimize probe accessibility when attaching bulky fluorophores or when targeting azide-functional biomolecular scaffolds. In research settings, it is often selected to generate DBCO-bearing probe intermediates that can be rapidly coupled to azide-tagged imaging partners, enabling efficient diversification of probe formats for microscopy, flow-based readouts, and imaging reagent libraries.

4. Multivalent Ligand And Platform Building

DBCO-PEG4-amine is well suited for generating multivalent ligand platforms and modular reagent architectures where controlled spacing between functional groups is important. The amine handle enables attachment to scaffold molecules, linkers, or polymer backbones, while the DBCO moiety provides a robust SPAAC coupling site for later reaction with azide-functional partners. This combination is widely used to build higher-order conjugates such as multivalent binding reagents, affinity capture tools, and reagent platforms that benefit from PEG-mediated flexibility and improved accessibility of reactive sites.