N-(Azido-PEG2)-N-Boc-PEG4-Boc | CAS 2093153-83-2

N-(Azido-PEG2)-N-Boc-PEG4-Boc is a PEG-based azide click chemistry reagent designed for bioorthogonal conjugation workflows. The molecule combines an azide handle with protected amine functionalities (Boc groups) and extended PEG spacers, enabling attachment to diverse targets while maintaining solubility and reducing nonspecific interactions. As an azide component, it is commonly incorporated into labeling, surface modification, and molecular imaging reagent development that rely on copper-catalyzed or strain-promoted azide–alkyne cycloaddition strategies.

1. Bioconjugation Linker Design

N-(Azido-PEG2)-N-Boc-PEG4-Boc is widely used as a PEGylated azide linker building block for constructing conjugates where a flexible, hydrophilic spacer is required to preserve target accessibility. Researchers incorporate this reagent into labeling reagents for proteins, peptides, and other biomolecular scaffolds by installing the azide functionality at the desired position, followed by downstream click coupling to alkyne-bearing partners. The Boc-protected groups support controlled functionalization during conjugate assembly, which is particularly valuable in multi-step workflows where sequential derivatization and intermediate handling are needed. Its PEG architecture also helps improve dispersion in aqueous labeling buffers, supporting reproducible conjugate preparation for research-scale assay development and materials studies.

2. Surface Modification And Coatings

N-(Azido-PEG2)-N-Boc-PEG4-Boc is used to introduce azide functionality onto surfaces and interfaces for subsequent click-based immobilization of biomolecules or affinity ligands. Materials scientists and biomaterials groups employ the reagent to create PEG-rich linkers on substrates such as polymer films, hydrogel surfaces, and functionalized nanoparticles, enabling later attachment of alkyne-functional capture agents through click coupling. The PEG spacers are commonly selected to reduce steric hindrance and limit nonspecific adsorption, which is important for building stable, well-characterized functional surfaces used in biosensing, binding studies, and platform prototyping. In industrial chemical applications, this type of azide-PEG linker is also leveraged for modular assembly of functional coatings where robust, orthogonal attachment chemistry is required.

3. Molecular Imaging Probe Assembly

N-(Azido-PEG2)-N-Boc-PEG4-Boc serves as a key intermediate for preparing azide-containing imaging probes and traceable reagent constructs that are assembled via click chemistry. Probe developers use the reagent to append an azide handle onto PEGylated scaffolds, allowing rapid coupling to alkyne-functional fluorophores, reporter tags, or imaging moieties during probe finalization. The PEG chain length and hydrophilic character are frequently chosen to improve probe solubility and to help maintain favorable presentation of the labeling group in complex labeling media. This modular design supports efficient iteration of probe formats in research and diagnostic reagent development pipelines, where interchangeable reporter components are coupled to a common azide-bearing backbone.

4. Diagnostic Reagent And Assay Platforms

N-(Azido-PEG2)-N-Boc-PEG4-Boc is applied in the construction of assay-ready reagent components that require orthogonal conjugation handles for consistent assay assembly. In diagnostic reagent development and analytical chemistry workflows, azide-PEG linkers are used to integrate capture elements, secondary reporters, or standardized labeling fragments into multi-component assay systems through click coupling to alkyne-bearing reagents. The reagent’s PEG-rich structure supports aqueous compatibility and helps create conjugates with controlled spacing between functional groups, which can be critical for minimizing background signal and maintaining reproducible binding geometries in platform development. Its protected functional groups also support flexible intermediate handling during reagent synthesis, enabling streamlined manufacturing of benchtop assay kits and research-use analytical tools.