bis-PEG23-endo-BCN | CAS 2152700-22-4

bis-PEG23-endo-BCN is a bis-functional, polyethylene glycol (PEG)-based click chemistry reagent featuring endo-bicyclononyne (BCN) groups for strain-promoted azide–alkyne cycloaddition (SPAAC). The PEG spacer architecture provides water-compatible handling and enables multivalent presentation of reactive BCN termini, which is particularly useful when conjugation density and solubility strongly influence downstream labeling or material assembly. bis-PEG23-endo-BCN is commonly selected for research workflows that require robust, catalyst-free click coupling to azide-bearing biomolecules, polymers, or surfaces.

1. Multivalent Biomolecule Labeling

bis-PEG23-endo-BCN is widely used to generate high-density BCN-functional linkers for labeling azide-modified proteins, peptides, antibodies, or protein scaffolds in chemical biology and molecular imaging workflows. The bis-PEG design helps maintain solubility and reduces aggregation during conjugation, supporting consistent reagent-to-biomolecule coupling in labeling pipelines. Researchers often choose this format when they need improved conjugation stoichiometry or when multivalent attachment can enhance signal uniformity across probe batches.

2. Bioorthogonal Surface Conjugation

bis-PEG23-endo-BCN supports azide-reactive surface engineering for creating BCN-functional coatings and patterned interfaces on assay platforms, microarrays, and biosensor surfaces. Its PEG-mediated spacing is valuable for tuning surface accessibility of reactive sites, which can affect how efficiently azide groups on immobilized capture reagents are engaged. This reagent format is frequently employed in diagnostic reagent development and analytical tool construction where reproducible surface chemistry and low-background labeling conditions are critical.

3. Hydrogel and Polymer Network Functionalization

bis-PEG23-endo-BCN is used to incorporate SPAAC-reactive BCN termini into PEG-based hydrogels and polymer networks that contain azide handles, enabling post-fabrication functionalization without harsh conditions. The bis-PEG architecture allows researchers to introduce crosslinking or modular attachment points while preserving water compatibility and processability during material preparation. Such BCN–azide click strategies are commonly adopted in biomaterials science to create tunable, chemically addressable polymer systems for imaging probes, affinity components, and structurally defined composite materials.

4. Imaging Probe and Reporter Construction

bis-PEG23-endo-BCN is a practical BCN building block for constructing azide-reactive imaging probes and fluorescent or luminescent reporters where controlled conjugation geometry matters. The PEG spacer can improve probe handling in aqueous labeling buffers and help manage steric effects that influence labeling efficiency and probe stability during purification. In molecular imaging and assay development, this reagent is often selected to assemble multicomponent reporter constructs by linking azide-bearing targeting elements to BCN-functional reporter scaffolds under catalyst-free conditions.