Iodo-PEG3-Azide | CAS 1309457-01-9

Iodo-PEG3-Azide is a PEG-linked azide reagent that combines an alkyl iodide handle with a terminal azide for orthogonal bioconjugation workflows. As a click chemistry building block, it is commonly used in strain-promoted or copper-catalyzed azide–alkyne cycloaddition formats to install functional payloads onto biomolecules, surfaces, and polymeric materials. The short PEG3 spacer improves aqueous compatibility and helps maintain accessibility of the azide moiety for downstream labeling and imaging applications.

1. Biomolecule Azide Labeling

Iodo-PEG3-Azide is widely used to introduce an azide functionality onto proteins, peptides, and other biomolecular scaffolds via the iodide-bearing PEG handle, enabling subsequent click-based attachment of probes, affinity tags, or imaging reporters. Research groups frequently select this reagent when they need a compact PEG spacer to reduce steric hindrance and preserve binding or recognition behavior of the target biomolecule during labeling workflows. The resulting azide-functional conjugates are then compatible with downstream click chemistry strategies used in chemical biology tool development and analytical assay construction.

2. Surface And Material Functionalization

Iodo-PEG3-Azide supports azide installation on polymer surfaces, resin-bound materials, and engineered interfaces where azide groups serve as versatile handles for later coupling. In materials science and biomaterials research, the PEG3 spacer helps promote uniform presentation of the azide for efficient capture by complementary alkyne-bearing ligands, crosslinkers, or fluorescent reporters. This approach is commonly used to generate functional coatings, patterned labeling platforms, and modular material systems that can be reconfigured through iterative click conjugation steps.

3. Molecular Imaging Probe Preparation

Iodo-PEG3-Azide is used in the preparation of modular molecular imaging probes by converting a target scaffold into an azide-bearing intermediate that can be rapidly coupled to imaging-compatible partners. Chemical biology laboratories often rely on this reagent to streamline probe assembly, particularly when the imaging reporter is introduced in a separate step using azide–alkyne click chemistry. The PEG3 chain contributes to improved solubility and accessibility, which can be advantageous when constructing multi-component probe libraries for fluorescence-based assays, microscopy labeling, or other optical readouts.

4. Diagnostic Reagent And Assay Platforms

Iodo-PEG3-Azide is applicable to the construction of diagnostic reagent platforms where azide-functional components are needed for standardized, high-specificity coupling to detection chemistries. Assay developers use azide intermediates to attach fluorophores, enzyme labels, or affinity reagents through click-compatible partners under controlled labeling conditions. The PEG3 spacer and reactive iodide handle make it useful for generating consistent conjugation-ready reagents that integrate smoothly into workflow-driven assay manufacturing and research screening pipelines.