Azido-PEG3-SS-PEG3-azide | CAS 1310827-27-0

Azido-PEG3-SS-PEG3-azide is a PEG-based, disulfide-containing bis-azide crosslinker designed for copper-free or copper-catalyzed azide–alkyne click chemistry workflows. The molecule features two terminal azide handles separated by a central reducible disulfide and flexible PEG spacers, enabling modular assembly of functional networks, linkers, and multivalent probes. Its bifunctional architecture makes it particularly relevant for constructing thiol-responsive conjugates, surface coatings, and imaging or materials platforms that benefit from controlled reducibility.

1. Multivalent Bioconjugation

Azido-PEG3-SS-PEG3-azide is widely used to generate multivalent conjugates for chemical biology and biomaterials research, where two click-reactive azide termini allow simultaneous coupling to complementary alkyne-bearing partners. Researchers employ it to bridge biomolecules such as proteins, peptides, and nucleic-acid scaffolds that have been functionalized with terminal alkynes, improving effective local concentration and enabling higher-order labeling strategies. The central disulfide provides an additional design element for workflows that require reducible linkage behavior during downstream processing or cellular uptake studies, while the PEG spacers help maintain solubility and reduce nonspecific interactions during probe preparation.

2. Thiol-Responsive Linkers

Azido-PEG3-SS-PEG3-azide serves as a practical reducible linker for constructing thiol-responsive assemblies in research settings, including platforms where cleavage of the disulfide is used to modulate conjugate architecture. Because the reagent presents two azide groups at controlled distances, it is commonly selected to connect two alkyne-functional components while preserving flexibility and minimizing steric constraints. This makes it useful for preparing switchable materials, detachable surface modifications, and probe formats where linker lability is a key variable in experimental design.

3. Click-Engineered Hydrogels

Azido-PEG3-SS-PEG3-azide is frequently incorporated into hydrogel and polymer network design for click-assembled biomaterials, particularly when researchers need a reducible crosslinking motif and two-point connectivity. By coupling its azide termini to alkyne-functional polymer backbones or crosslinkers, teams can build networks that are compatible with aqueous processing and modular functionalization. The PEG spacers support uniform gel formation and tunable mechanical behavior, while the disulfide linkage introduces a chemically defined handle for post-assembly responsiveness in materials characterization and scaffold development.

4. Molecular Imaging Probes

Azido-PEG3-SS-PEG3-azide is used as a multivalent click handle for preparing imaging and detection probes that require controlled spacing between functional moieties. In molecular imaging reagent development, the reagent’s two azide groups enable sequential or parallel attachment of alkyne-bearing targeting ligands, affinity tags, or reporter components, supporting consistent probe architecture and improved conjugation efficiency in complex labeling schemes. The PEG-based structure helps maintain colloidal stability and reduces aggregation during probe formulation, while the reducible disulfide can be leveraged to create probe constructs with defined linker chemistry for downstream experimental workflows.