Bromo-PEG2-azide | CAS 530151-56-5

Bromo-PEG2-azide is a PEG-based bifunctional reagent combining an azide for copper-free or copper-mediated click chemistry with a terminal bromo handle for electrophilic conjugation or surface functionalization. As a click chemistry building block, its flexible ethylene glycol spacer helps reduce steric constraints during labeling and improves compatibility with aqueous bioconjugation workflows. The bromo-azide motif makes it particularly useful when researchers need a single reagent that can be incorporated into larger constructs, then later used to attach probes, biomolecules, or materials through azide-reactive click handles.

1. Surface And Material Labeling

Bromo-PEG2-azide supports the functionalization of polymeric and inorganic surfaces where an azide-bearing PEG linker is advantageous for downstream attachment of fluorescent tags, affinity ligands, or imaging reagents. The bromo functionality provides a reactive handle for coupling to nucleophilic sites on pre-functionalized substrates, while the PEG2 spacer helps maintain accessibility of the azide group for subsequent click-based grafting. This dual-reactive design is commonly used in materials chemistry and chemical biology to create modular interfaces for sensor platforms, biointerfaces, and surface-tethered libraries.

2. Biomolecule PEGylation Handles

Bromo-PEG2-azide is used as a PEG linker for preparing azide-functional bioconjugates, enabling controlled attachment of PEG spacers to proteins, peptides, or other biomolecular scaffolds that have been pre-equipped with nucleophilic coupling sites. The reagent’s PEG2 segment can improve solubility and reduce nonspecific interactions in labeling workflows, while preserving a reactive azide for later click conjugation to dyes, affinity tags, or reporter groups. Researchers in chemical biology and molecular imaging frequently select this class of bifunctional PEG linkers to streamline build-to-order probe synthesis.

3. Imaging Probe Conjugation

Bromo-PEG2-azide is well suited for constructing azide-functional imaging probes that are assembled from separate targeting and reporting components. After incorporation of the reagent into a probe scaffold, the azide handle enables efficient click attachment of fluorophores or other imaging reporters under labeling conditions compatible with sensitive biomolecular formats. The presence of the bromo group allows the initial installation of the PEG2-azide moiety onto the desired carrier, supporting modular probe generation for microscopy, flow-based detection reagents, and other visualization tool development.

4. Diagnostic Reagent Building Blocks

Bromo-PEG2-azide is commonly used to prepare azide-functional components for diagnostic reagent development, including multivalent binding reagents and assay labeling constructs. By installing the PEG2-azide motif onto a capture molecule, polymer backbone, or scaffold, teams can later use click chemistry to attach detection reporters with consistent stoichiometry and predictable conjugation sites. This approach aligns with common downstream workflows in assay chemistry, where modular assembly and standardized labeling strategies help accelerate reagent iteration and optimization.