Sulfo DBCO-PEG3-NHS ester

Sulfo DBCO-PEG3-NHS ester is a water-soluble, PEGylated DBCO (dibenzocyclooctyne) click reagent designed for strain-promoted azide–alkyne cycloaddition (SPAAC) workflows and for efficient conjugation to primary amines via an NHS ester handle. Its amphiphilic sulfonated character and short PEG spacer support compatibility with aqueous bioconjugation environments while minimizing steric effects during subsequent click labeling. As a modular “click-ready” linker, it is widely used to install DBCO onto proteins, peptides, antibodies, and other amine-containing biomolecules, enabling downstream attachment of azide-bearing reporters, probes, or materials.

1. Protein And Peptide Labeling

Sulfo DBCO-PEG3-NHS ester is commonly used to functionalize proteins and peptides with a DBCO handle for later SPAAC coupling to azide-functional partners. Researchers and diagnostic reagent developers rely on the NHS ester chemistry to target lysine residues and N-termini under standard bioconjugation conditions, producing stable amide-linked DBCO conjugates that can be stored and handled as click reagents. The sulfonated PEG spacer improves aqueous handling and helps maintain conjugation performance in labeling buffers used for imaging probe preparation, affinity reagent generation, and workflow automation in assay development.

2. Antibody Conjugation Workflows

Sulfo DBCO-PEG3-NHS ester supports antibody and antibody-fragment labeling strategies where a robust, catalyst-free click handle is required for assembling multivalent binders. In molecular imaging and chemical biology laboratories, DBCO installation via the NHS ester step enables subsequent attachment of azide-containing fluorophores, affinity tags, or polymeric scaffolds while avoiding copper-mediated conditions that can complicate sensitive biomolecules. The PEG3 linker is frequently selected to balance accessibility of the DBCO group with preservation of binding-site behavior during probe construction and conjugate library generation.

3. Surface and Material Functionalization

Sulfo DBCO-PEG3-NHS ester is used to introduce DBCO functionality onto amine-bearing surfaces and biomaterial interfaces, enabling SPAAC-based immobilization of azide-tagged components. Biomaterials groups apply the NHS ester to coat or functionalize substrates such as polymer films, hydrogel matrices, and biofunctionalized carriers that present primary amines, then use the resulting DBCO layer to capture azide-functional ligands, imaging reporters, or affinity molecules. This approach is particularly valued in materials assembly workflows where modular “orthogonal” coupling is needed to build multilayer constructs without relying on metal catalysts.

4. Diagnostic And Imaging Probe Assembly

Sulfo DBCO-PEG3-NHS ester is frequently incorporated into the reagent supply chain for building diagnostic and imaging probes that require precise modular conjugation. After DBCO installation on a targeting scaffold or carrier, downstream SPAAC with azide-bearing dyes, nanoparticles, or chelator-containing reporters allows rapid interchange of labeling components across probe formats. The water-soluble PEGylated design helps maintain reagent practicality in typical probe-preparation buffers, supporting consistent conjugate generation for research-grade imaging reagent development and assay reagent optimization.