Propargyl-PEG1-SS-PEG1-C2-Boc | CAS 1807518-78-0

Propargyl-PEG1-SS-PEG1-C2-Boc is a PEG-based bifunctional click chemistry reagent designed for copper-free and/or copper-assisted conjugation workflows, featuring a terminal propargyl (alkyne) handle for bioorthogonal coupling and a central disulfide (SS) linkage that supports redox-responsive material design. The molecule also incorporates PEG spacers to improve aqueous compatibility and a protected C2-Boc functionality that can be leveraged for downstream derivatization and controlled reactivity in complex labeling strategies. This reagent is commonly selected for constructing modular PEG conjugates, affinity probes, and imaging or delivery research tools where stable circulation-like behavior in aqueous media and later intracellular or microenvironmental disassembly are desirable design features.

1. Redox-Responsive Probe Labeling

Propargyl-PEG1-SS-PEG1-C2-Boc is widely used to build redox-responsive chemical probes and labeling reagents for chemical biology studies that require a cleavable disulfide motif within a PEG scaffold. Researchers incorporate the alkyne handle to attach the probe to azide-functional targets such as biomolecular ligands, affinity tags, or polymeric carriers, while the SS linkage provides a design route to trigger structural changes under reducing conditions encountered in cellular compartments. The PEG spacers help maintain solubility and reduce nonspecific interactions, making the reagent suitable for preparing water-compatible conjugates for imaging reagent development and mechanistic studies of intracellular trafficking and cargo release.

2. Bioorthogonal Surface Conjugation

Propargyl-PEG1-SS-PEG1-C2-Boc supports the preparation of azide-reactive surfaces and functional coatings used in biosensing and biomaterials research. Laboratories use the propargyl functionality to couple the reagent to azide-bearing biomolecule layers, hydrogel networks, or patterned surfaces, enabling stable attachment of PEGylated, disulfide-containing linkers that can be further processed for assay workflows. The disulfide segment is particularly attractive for creating materials where linker cleavage can modulate accessibility or release of attached components, and the PEG1 spacers contribute to reduced fouling and improved wetting on biomaterial interfaces.

3. Modular PEG Conjugate Building

Propargyl-PEG1-SS-PEG1-C2-Boc is a practical building block for assembling modular PEG conjugates used across molecular imaging, diagnostic reagent development, and chemical tool synthesis. The reagent’s terminal alkyne enables straightforward incorporation into larger conjugate architectures through click coupling to azide-functional partners, including PEGylated imaging scaffolds, affinity reagents, and multi-component research constructs. The presence of PEG spacers supports consistent solvation and controlled spacing between functional groups, while the disulfide linkage offers a chemically meaningful handle for designing conjugates with tunable stability profiles during downstream processing and storage.

4. Linker-Enabled Imaging Reagent Design

Propargyl-PEG1-SS-PEG1-C2-Boc is commonly selected in molecular imaging reagent design workflows where a cleavable, PEG-based linker is needed to connect imaging moieties or targeting ligands to a conjugate platform. Teams in chemical biology and imaging chemistry use the propargyl group to attach the reagent to azide-functional imaging components or carriers, producing constructs with improved aqueous handling and reduced aggregation. The SS linkage provides a structural design element that can be exploited to create conjugates with environment-dependent behavior, supporting the development of research-grade imaging tools and labeling reagents used to study probe localization, cargo processing, and conjugate stability in complex experimental systems.