Azido-PEG5-Ala-Ala-Asn-PAB | CAS 2055048-54-7

Azido-PEG5-Ala-Ala-Asn-PAB is a PEG-linked azide-containing peptide–PAB conjugate designed for use in copper-free and copper-catalyzed azide–alkyne click chemistry workflows. The reagent combines a flexible PEG5 spacer with a short peptide sequence and a p-aminobenzyl (PAB) motif, enabling modular attachment of the azide handle to biomolecules, targeting ligands, or imaging/functional reporters. In research and materials settings, this structure is commonly selected to introduce a defined clickable site while maintaining solubility and bioconjugation compatibility for downstream conjugate assembly.

1. Targeted Probe Conjugation

Azido-PEG5-Ala-Ala-Asn-PAB is frequently used as an azide-bearing linker to build targeted chemical probes by click attachment to alkyne-functional reporters such as fluorophores, affinity tags, or enriched detection handles. The PEG5 spacer helps minimize steric constraints during conjugate assembly, supporting consistent labeling of proteins, peptides, or nucleic-acid-binding scaffolds used in chemical biology and assay development. Researchers often choose this reagent when they need a stable, modular clickable unit that can be incorporated into probe libraries while preserving aqueous compatibility and maintaining a defined distance between the cargo and the reactive site.

2. Enzyme-Responsive Linker Platforms

Azido-PEG5-Ala-Ala-Asn-PAB is well suited for constructing enzyme-responsive or cleavage-associated linker platforms in biomaterials and molecular imaging toolkits, where the PAB-containing segment is used as a functional motif within larger conjugates. By installing the azide handle via click chemistry, teams can position the responsive linker within larger architectures such as multicomponent imaging constructs, activatable signal reporters, or material-bound sensing elements. This reagent is commonly integrated into design strategies that require orthogonal modular assembly, allowing the clickable azide to be introduced early and then coupled to alkyne-functional components as the overall platform is finalized.

3. PEGylated Biomolecule Labeling

Azido-PEG5-Ala-Ala-Asn-PAB supports PEGylated labeling approaches in which the PEG5 chain improves solubility and reduces aggregation during conjugation and subsequent handling. The azide functionality enables straightforward coupling to alkyne-functional biomolecules or surfaces, making the reagent useful for preparing well-defined conjugates for biochemical workflows, binding studies, and reagent development. In practical laboratory use, this product is selected when researchers want a clickable PEG-peptide module that can be incorporated into conjugation schemes without requiring extensive redesign of existing alkyne-bearing partners.

4. Surface and Hydrogel Functionalization

Azido-PEG5-Ala-Ala-Asn-PAB is used to functionalize surfaces and soft materials by click attachment to alkyne-modified substrates, including polymer films, beads, and hydrogel scaffolds. The PEG5 spacer and peptide/PAB segment provide a convenient handle for incorporating bioactive or responsive motifs into material architectures while maintaining compatibility with aqueous processing conditions. Material scientists and diagnostic-reagent developers often rely on this reagent to introduce a defined azide functionality that can be coupled to alkyne-functional capture ligands, imaging tags, or signal transduction elements, enabling modular fabrication of research-grade functional materials.