Alkyne-PEG13-NHS

Alkyne-PEG13-NHS is a PEG-based NHS ester click chemistry reagent combining an activated N-hydroxysuccinimide (NHS) ester for efficient amide bond formation with a terminal alkyne for subsequent copper-catalyzed azide–alkyne cycloaddition (CuAAC). The extended PEG13 spacer provides aqueous compatibility and steric control, which is valuable when labeling proteins, peptides, or other amine-containing biomolecules with minimal aggregation and improved conjugate solubility. This bifunctional design is widely used to prepare click-ready bioconjugates for downstream attachment to azide-bearing probes, surfaces, or biomaterials.

1. Protein Surface Labeling

Alkyne-PEG13-NHS is commonly used to introduce click handles onto proteins and antibody fragments by reacting the NHS ester with accessible primary amines on lysine residues or N-termini. The PEG13 spacer helps maintain conjugate stability in aqueous buffers and can reduce nonspecific hydrophobic interactions that otherwise complicate labeling workflows. Researchers use the resulting alkyne-functionalized biomolecules as versatile building blocks for subsequent CuAAC coupling to azide-functional dyes, affinity tags, or imaging reagents, enabling modular probe assembly for biochemical assays and molecular imaging development.

2. Targeting Ligand Conjugation

Alkyne-PEG13-NHS supports the preparation of click-compatible targeting ligands, including peptides, enzyme substrates, and other amine-bearing recognition elements, where a terminal alkyne is required for orthogonal attachment to azide-functional partners. The NHS ester chemistry makes it straightforward to functionalize ligands under typical bioconjugation conditions, while the PEG13 chain improves solubility and helps preserve binding-relevant behavior during labeling and storage. Downstream, the alkyne handle enables efficient conjugation to azide-decorated nanoparticles, multivalent scaffolds, or imaging/diagnostic components, facilitating rapid iteration of ligand formats in research and industrial R&D settings.

3. PEGylated Material Functionalization

Alkyne-PEG13-NHS is frequently applied in biomaterials science to functionalize polymeric surfaces and hydrogel components that present accessible amine groups, generating stable, click-reactive interfaces. The PEG spacer is particularly useful for controlling surface charge and hydration, which can influence nonspecific adsorption and cell-interaction background in materials workflows. After immobilization or conjugation, the terminal alkyne provides a handle for CuAAC attachment to azide-bearing crosslinkers, fluorescent reporters, or affinity moieties, supporting the fabrication of patterned materials and tunable composite systems for materials characterization and assay development.

4. Imaging Probe Assembly

Alkyne-PEG13-NHS is used to generate alkyne-bearing biomolecular components that serve as precursors for assembling fluorescent and luminescent imaging probes via click coupling to azide-functional reporters. The reagent’s PEG13 linker is advantageous when constructing probe conjugates that need improved aqueous behavior and reduced aggregation, especially for multicomponent labeling strategies. By converting amine-containing targets into click-ready alkyne conjugates, teams can streamline probe synthesis and optimize labeling stoichiometry through modular CuAAC pairing with azide dyes, quencher units, or other imaging-relevant tags used in molecular imaging and analytical research workflows.