Azido-PEG4-Amido-Tris | CAS 1398044-55-7

Azido-PEG4-Amido-Tris is a PEG-based azide click chemistry reagent featuring an azido functional group for bioorthogonal conjugation and an amide-linked Tris motif that supports aqueous handling and stable coupling into biomolecular and surface chemistries. As an azide-bearing component, it is commonly used in strain-promoted or copper-catalyzed azide–alkyne cycloaddition workflows to introduce a flexible, hydrophilic PEG spacer that can improve solubility and reduce steric constraints in labeling, immobilization, and probe assembly. Its modular structure makes it a practical building block for preparing PEGylated conjugates, functional linkers, and reagent-ready materials used across chemical biology, diagnostics development, and biomaterials research.

1. Protein And Peptide Labeling

Azido-PEG4-Amido-Tris is used as a click handle to install PEG spacers onto proteins and peptides for downstream conjugation to imaging tags, affinity ligands, or polymeric reporters. Researchers frequently incorporate this azide reagent into labeling strategies where maintaining aqueous compatibility and minimizing nonspecific interactions are important, especially when attaching bulky fluorophores or multivalent recognition elements. The PEG4 segment helps preserve target accessibility after conjugation, making the resulting azide-bearing intermediates convenient for assembling probe panels and standardized reagent lots for comparative studies.

2. Biomolecule Surface Functionalization

Azido-PEG4-Amido-Tris supports immobilization and surface patterning workflows where azide functionality is required for subsequent click coupling to alkyne-modified surfaces, nanoparticles, or patterned substrates. In biomaterials and interface engineering, the PEG spacer is valued for improving hydration at the material boundary and for moderating steric effects that can otherwise reduce binding or labeling efficiency. This makes Azido-PEG4-Amido-Tris a practical reagent for preparing functional coatings, assay-compatible surfaces, and modular interfaces used in chemical biology tool development and materials characterization.

3. Imaging Probe And Reporter Assembly

Azido-PEG4-Amido-Tris is widely used to generate azide-functional intermediates for assembling molecular imaging probes and analytical reporters via click conjugation to alkyne-bearing dyes, chelators, or scaffolded reporter groups. The reagent’s PEG-based linker is particularly useful when constructing probes that require improved dispersion in aqueous buffers and reduced aggregation tendencies. By providing a defined azide moiety with a flexible spacer, Azido-PEG4-Amido-Tris helps streamline the production of multi-component reagent sets used in fluorescence-based assays, imaging reagent optimization, and labeling chemistry screening.

4. Diagnostic Reagent And Assay Reagents

Azido-PEG4-Amido-Tris is employed in the development of diagnostic reagent components and assay-ready constructs where controlled conjugation chemistry is needed to attach detection motifs to carriers. The azide group enables reliable downstream coupling to alkyne-functional reporter systems, while the PEG4 spacer supports consistent reagent behavior in common assay buffers and reduces steric crowding near the attachment point. Chemical biology and diagnostics-focused laboratories use Azido-PEG4-Amido-Tris to build modular conjugates for signal generation workflows, including reagent standardization for multiplexing and platform compatibility across different assay formats.