Azido-PEG7-amine | CAS 1333154-77-0

Azido-PEG7-amine is a polyethylene glycol (PEG)-based linker bearing a terminal azide and a primary amine, enabling bioorthogonal click chemistry conjugation alongside versatile handle-based coupling strategies. As a classic azide functional group, it is commonly used in copper-free or copper-catalyzed azide–alkyne cycloaddition workflows to attach biomolecules, targeting ligands, or imaging moieties to surfaces and carriers. The PEG7 spacer provides aqueous compatibility and distance control, while the amine supports downstream derivatization for labeling, immobilization, or incorporation into multifunctional reagent platforms.

1. Bioconjugation Linker Use

Azido-PEG7-amine is widely used as a modular PEG spacer for preparing azide-functional bioconjugates, including PEGylated probes and conjugates that require controlled hydrophilicity and reduced steric crowding. Researchers incorporate the azide handle to enable efficient attachment to alkyne-bearing partners such as cyclooctyne- or DBCO-functional tags, affinity ligands, or reporter groups used in chemical biology workflows. The terminal amine provides an additional orthogonal functional site for coupling to activated esters, isothiocyanates, or other amine-reactive chemistries, supporting multi-step assembly of complex constructs used in assay development and molecular imaging reagent preparation.

2. Surface Immobilization Chemistry

Azido-PEG7-amine is frequently selected for functionalizing polymeric or biomaterial surfaces where a PEG spacer improves wettability and minimizes nonspecific interactions. The azide group enables subsequent click-based grafting of alkyne-functional coatings, capture reagents, or fluorescent reporters onto substrates such as microarrays, sensor platforms, and patterned materials. The primary amine can be used to anchor the linker to surfaces via amide-forming coupling or to introduce additional reactive functionality prior to click attachment, making Azido-PEG7-amine a practical building block for constructing stable, modular interfaces in research-grade diagnostic and analytical systems.

3. Molecular Imaging Probe Assembly

Azido-PEG7-amine is commonly employed in the build-out of imaging and detection probes that require a flexible, water-soluble spacer between a biomolecule and a reporter. The azide functionality supports click conjugation to alkyne-bearing fluorophores, quencher systems, or imaging tags, enabling rapid interchange of labeling components during probe optimization. The PEG7 chain helps maintain solubility and can reduce local aggregation effects around the conjugation site, while the amine handle supports attachment to carrier proteins, peptides, or scaffold materials used to generate imaging reagent libraries for microscopy, flow-based assays, and platform screening.

4. Diagnostic Reagent Platform Building

Azido-PEG7-amine is used as a linker component in diagnostic reagent development where modular assembly and reliable surface or bead functionalization are required. The azide group allows click attachment of alkyne-functional recognition elements, signal reporters, or capture chemistries to create customizable reagent formats for analytical workflows. The presence of a primary amine enables pre-functionalization steps such as coupling to carrier matrices, conjugation to scaffold molecules, or incorporation into multi-functional reagent architectures, supporting the creation of reproducible, chemically addressable platforms used in assay prototyping and reagent kit development.