Bis-propargyl-PEG12 | CAS 1351373-50-6

Bis-propargyl-PEG12 is a PEG-based bifunctional linker bearing two terminal propargyl groups, designed for copper-free or copper-catalyzed azide–alkyne click chemistry conjugation workflows. The long, flexible PEG spacer supports solubility and reduces nonspecific interactions, making it a common choice for building modular bioconjugates, surface coatings, and imaging/assay reagents. Its two reactive termini enable rapid installation of two azide handles or integration into multi-component constructs where defined spacing and aqueous compatibility are important.

1. Bioconjugate Linker Use

Bis-propargyl-PEG12 is widely used as a PEG spacer linker in bioconjugation projects that require connecting two azide-bearing biomolecules, affinity ligands, or polymeric components while maintaining colloidal stability in aqueous buffers. Researchers employ the bifunctional propargyl architecture to generate multivalent conjugates for assay development, reagent labeling, and workflow-compatible reagent assembly, where the PEG length helps preserve accessibility of functional groups and improves handling of the final conjugate. The two-click design also supports sequential or parallel conjugation strategies in research-grade labeling pipelines, including preparation of standards and control materials.

2. Surface Immobilization Chemistry

Bis-propargyl-PEG12 supports click-based immobilization on azide-functionalized surfaces and substrates, including polymer films, hydrogel matrices, and planar sensor platforms. In materials and biosensor development, the PEG spacer helps tune surface hydration and reduces steric crowding, which is valuable when immobilizing capture molecules or creating antifouling interfaces. By using azide-presenting surfaces paired with the bis-propargyl linker, teams can build stable, modular coatings with controlled linker length and improved reproducibility across batches of surface-prepared reagents.

3. Molecular Imaging Probe Building

Bis-propargyl-PEG12 is commonly incorporated into molecular imaging and labeling reagent development as a flexible PEG tether that connects imaging tags, reporter moieties, or targeting components bearing complementary click handles. The bifunctional propargyl groups allow straightforward assembly of multi-component probe architectures, including constructs where spacing between a targeting element and a reporter is important for maintaining binding accessibility and minimizing aggregation. This linker format is also used to prepare probe libraries for optimization studies in chemical biology and molecular imaging toolkits, where modularity and aqueous compatibility streamline iterative design.

4. Polymer and Hydrogel Functionalization

Bis-propargyl-PEG12 is used to introduce click-reactive functionality into polymer systems and hydrogel networks for creating tunable, modular materials. Materials scientists and biomaterials teams employ the PEG spacer to incorporate bioorthogonal handles that can later be coupled to azide-functional crosslinkers, cell-interactive ligands, or fluorescent reporters, enabling stepwise construction of functional biomaterials. The dual propargyl termini support formation of defined tethering patterns within polymer architectures, supporting reproducible labeling density and improved solubility during material processing and downstream characterization.