Azido-PEG5-succinimidyl carbonate | CAS 1402411-88-4

Azido-PEG5-succinimidyl carbonate is a bifunctional PEG-based click chemistry reagent that combines an azide handle for copper-free or copper-mediated azide–alkyne cycloaddition with an N-hydroxysuccinimide (NHS) carbonate electrophile for efficient reaction with primary amines. The reagent’s PEG5 spacer supports improved solubility and reduced steric constraints, which is valuable when preparing conjugates for labeling, immobilization, and surface functionalization. Because it couples robust amine-reactivity with a widely used click handle, it is frequently selected for building modular bioconjugates, imaging probes, and functional biomaterials from amine-bearing proteins, peptides, and polymeric scaffolds.

1. Antibody And Protein Labeling

Azido-PEG5-succinimidyl carbonate is commonly used to introduce a clickable azide functionality onto antibodies and other amine-containing proteins while maintaining a flexible PEG spacer between the biomolecule and the reactive site. Researchers in chemical biology and molecular imaging workflows use the NHS carbonate to generate azide-modified protein conjugates that can subsequently be coupled to complementary alkyne-bearing tags, probes, or carrier molecules. This approach supports modular assembly of multivalent labeling reagents, including conjugates designed for flow cytometry reagents, immunoassay components, and imaging toolkits where controlled functionalization of the protein surface is important.

2. Surface And Bead Immobilization

Azido-PEG5-succinimidyl carbonate is well suited for functionalizing solid supports such as agarose beads, magnetic beads, and microarray surfaces that present accessible primary amines or are pre-treated to introduce amine groups. The NHS carbonate enables stable attachment of the PEG-azide moiety to the solid phase, creating a reusable platform for subsequent click-based immobilization of alkyne-functional ligands, capture reagents, or detection handles. In diagnostic reagent development and assay manufacturing settings, this strategy is often used to generate patterned or batch-produced clickable surfaces for constructing workflows such as affinity capture panels, multiplex binding assays, and modular diagnostic reagent components.

3. PEGylated Peptide And Biomolecule Conjugates

Azido-PEG5-succinimidyl carbonate is frequently applied to derivatize peptides, enzyme substrates, and other small biomolecules that contain primary amines, enabling installation of an azide group for downstream click conjugation. The PEG5 spacer helps mitigate aggregation and can improve handling of conjugates in aqueous labeling buffers, which is particularly useful when preparing libraries of clickable biomolecule derivatives. Chemical biology teams use the reagent to generate azide-functional building blocks that can be clicked to fluorophores, affinity tags, or carrier scaffolds, supporting construction of probe sets for target engagement studies, pathway mapping tools, and structured reagent panels used in research instrumentation.

4. Biomaterials Functionalization For Probes

Azido-PEG5-succinimidyl carbonate is used to incorporate click-ready azide groups into biomaterial matrices and polymeric materials that can be modified through amine chemistry. The NHS carbonate provides a practical route to tether PEG-azide motifs onto amine-bearing hydrogels, coatings, and polymer surfaces, enabling later attachment of alkyne-functional imaging moieties, affinity ligands, or reporter elements via click chemistry. Biomaterials scientists and molecular imaging developers leverage this modular functionalization to create spatially addressable or composition-tunable materials for research-grade labeling, scaffold-based probe presentation, and fabrication of clickable interfaces for advanced assay formats.