Ald-CH2-PEG5-azide | CAS 1446282-38-7

Ald-CH2-PEG5-azide is a PEGylated azide-containing click chemistry reagent that combines an aldehyde functionality with a terminal azide for bioorthogonal conjugation workflows. As an azide-bearing handle, it is widely used in strain-promoted or copper-catalyzed azide–alkyne cycloaddition (CuAAC) strategies, while the aldehyde provides an additional reactive group for forming imine or hydrazone linkages with amine- or hydrazide-bearing partners. This dual-reactivity design makes the reagent particularly relevant for constructing modular conjugates, surface coatings, and imaging or labeling platforms where controlled attachment chemistry is required.

1. Bioconjugation Linker Chemistry

Ald-CH2-PEG5-azide is commonly used as a multifunctional linker in bioconjugation workflows that require both a PEG spacer and an orthogonal reactive group. The aldehyde moiety enables coupling to biomolecular amines (e.g., lysine-rich proteins or peptide tags) under standard aldehyde conjugation conditions, while the azide handle supports downstream installation of fluorescent dyes, affinity tags, or reporter groups via azide–alkyne click chemistry. The PEG5 spacer helps improve solubility and reduces nonspecific interactions in labeling and conjugate assembly, making the reagent a practical choice for constructing research-grade probe libraries and well-defined conjugate architectures.

2. Molecular Imaging Probe Assembly

Ald-CH2-PEG5-azide is frequently employed in molecular imaging reagent development where modular attachment of imaging reporters is needed. Researchers use the azide functionality to click onto alkyne-functional imaging moieties such as fluorophores or luminescent reporters, enabling rapid generation of probe panels from a common intermediate. The aldehyde group can be used to pre-functionalize biomolecule carriers or scaffold components before click coupling, supporting workflows that benefit from sequential conjugation steps and improved control over labeling density. This combination is especially useful when researchers want to tune probe properties through PEG-mediated spacing and orthogonal attachment chemistry.

3. Surface Coating And Materials Functionalization

Ald-CH2-PEG5-azide is used to functionalize biomaterials and engineered surfaces for applications that require stable presentation of azide groups and improved antifouling behavior. The aldehyde functionality can react with amine-containing coatings or surface-bound linkers, while the PEG5 chain provides spacing that can reduce steric hindrance and improve accessibility of the azide for subsequent click reactions. After surface immobilization, the azide enables patterned attachment of alkyne-bearing ligands, polymers, or reporter molecules through click chemistry, supporting the fabrication of functional materials such as assay substrates, capture surfaces, and research-grade biointerfaces.

4. Diagnostic Reagent And Assay Development

Ald-CH2-PEG5-azide is applied in diagnostic reagent and assay chemistry as a versatile intermediate for building labeled detection reagents and assay components. The reagent’s aldehyde group supports conjugation to amine-containing recognition elements or assay scaffolds, and the azide handle allows later coupling to detection reporters using azide–alkyne click chemistry. This two-stage strategy is frequently used to streamline reagent generation, enabling consistent reporter installation and facilitating the creation of multiplexed assay formats where different alkyne-functional reporters can be introduced to the same azide-bearing backbone.