Ald-CH2-PEG3-azide | CAS 1002342-83-7

Ald-CH2-PEG3-azide is an aldehyde-functionalized, PEG3-spaced azide click reagent designed for modular bioconjugation workflows. As a bifunctional handle, it combines an aldehyde group for orthogonal coupling chemistry with an azide moiety compatible with strain-promoted or copper-catalyzed azide–alkyne cycloaddition (click) strategies. The PEG3 linker supports aqueous solubility and helps reduce steric constraints when installing azide tags on biomolecules, surfaces, and polymeric materials. This reagent is commonly used to generate clickable conjugates for labeling, immobilization, and multistep assembly of imaging and analytical probes.

1. Biomolecule Labeling

Ald-CH2-PEG3-azide is widely used to introduce azide functionality onto proteins, peptides, and other biomacromolecules while maintaining a flexible PEG3 spacer for downstream click coupling. The aldehyde handle enables orthogonal attachment to amine-rich targets or other aldehyde-reactive labeling schemes used in research workflows, after which the azide group provides a robust handle for subsequent conjugation to alkynes in click reactions. This approach is particularly useful for preparing multicomponent probes where the azide tag must be installed first and then reacted with complementary alkyne-bearing dyes, affinity ligands, or reporter elements to generate defined conjugates for assay development and imaging reagent construction.

2. Surface And Material Functionalization

Ald-CH2-PEG3-azide supports azide installation on engineered materials and device surfaces, enabling patterned or batch functionalization for research-grade biomaterials and diagnostic reagent platforms. The aldehyde functionality provides a practical route for coupling to surfaces and coatings that can react with aldehydes or aldehyde-derivatized chemistries, while the PEG3 spacer helps maintain accessibility of the azide group after immobilization. Once attached, the azide serves as a click handle for linking to alkyne-functional polymers, hydrogel components, capture ligands, or fluorescent reporters, allowing researchers to build modular material architectures used in biosensing, surface-based assays, and immobilized reagent systems.

3. Multicolor Probe Assembly

Ald-CH2-PEG3-azide is used as a key intermediate for assembling multicolor or multiplexed labeling reagents in chemical biology and molecular imaging tool development. By installing azide groups onto a primary scaffold (such as a targeting biomolecule, polymer backbone, or nanoparticle precursor), the reagent enables sequential or parallel click conjugations with distinct alkyne-functional reporters. The PEG3 linker helps preserve reactivity and reduces steric hindrance, which is valuable when building complex probe sets that require consistent labeling density and reliable coupling to multiple reporter components. This workflow is commonly adopted for generating panel-based reagents used in fluorescence-based readouts, imaging experiments, and analytical assay optimization.

4. Polymer and Hydrogel Conjugation

Ald-CH2-PEG3-azide is frequently incorporated into polymer and hydrogel modification strategies to introduce azide sites for controlled click-based crosslinking or post-functionalization. The aldehyde functionality can be used to integrate the reagent into polymer backbones or to couple it to polymeric carriers that support aldehyde-reactive chemistries, while the azide group provides a stable, widely compatible handle for later reaction with alkyne partners. Researchers use this design to create clickable polymer networks, functional coatings, and carrier systems that can be decorated with fluorescent tags, affinity moieties, or other reporter groups through click coupling. The PEG3 spacing is especially helpful for maintaining accessibility of the azide within hydrated polymer environments where steric effects can limit conjugation efficiency.