Sulfo DBCO-PEG3-acid

Sulfo DBCO-PEG3-acid is a water-soluble DBCO (dibenzocyclooctyne) click chemistry reagent bearing a short PEG3 spacer and a terminal carboxylic acid. As a strain-promoted azide–alkyne cycloaddition (SPAAC) partner, it is widely used for copper-free bioconjugation and labeling workflows where azide-functional biomolecules, polymers, or surfaces need to be coupled under mild conditions. The PEG spacer and sulfonated character support aqueous handling, while the acid handle enables downstream attachment to amine-containing targets, polymer backbones, or solid supports during probe and material assembly.

1. Biomolecule Labeling

Sulfo DBCO-PEG3-acid is commonly used to generate azide-reactive-to-DBCO conjugates for labeling proteins, peptides, and nucleic-acid reagents in aqueous buffer systems. Researchers select this reagent when they need copper-free click compatibility to preserve sensitive functional groups or to simplify workflows that avoid Cu(I) exposure. The PEG3 spacer helps reduce steric constraints around the DBCO moiety, supporting efficient coupling to azide-bearing targets used in biochemical assays, affinity reagents, and imaging tool development.

2. Surface And Bead Conjugation

Sulfo DBCO-PEG3-acid is well suited for immobilization strategies where DBCO functionality is presented on beads, resins, or planar materials to capture azide-tagged components. The terminal carboxylic acid provides a practical anchoring handle for coupling to activated surfaces or for integrating into polymeric coatings, enabling modular build-outs of affinity platforms. This format is frequently adopted in assay development and workflow engineering, including preparation of clickable capture surfaces for enrichment, fractionation, and multistep assembly of complex reagent sets.

3. Molecular Imaging Probes

Sulfo DBCO-PEG3-acid is used in the construction of azide-functional imaging probes where SPAAC coupling provides a reliable route to install imaging reporters onto biomolecular scaffolds or probe carriers. The water-friendly PEG3 architecture supports probe solubility and helps maintain accessibility of the clickable DBCO group during conjugation and formulation. In molecular imaging reagent development, the carboxylic acid handle can also facilitate incorporation into probe linkers and polymer carriers, supporting reproducible probe assembly for fluorescence, luminescence, or other label-based readouts.

4. Polymer and Hydrogel Functionalization

Sulfo DBCO-PEG3-acid is applied to functionalize azide-bearing polymers, crosslinkable networks, and hydrogel materials for creating clickable, modular biomaterials. The reagent’s PEG spacer supports homogeneous presentation of DBCO groups in hydrated polymer environments, which is valuable for materials used in chemical biology and biomaterials research. The carboxylic acid functionality enables integration into polymer architectures and linker strategies, allowing researchers to build materials that can be further decorated with azide-tagged ligands, reporters, or bioactive motifs for downstream experimental customization.