Methyltetrazine-PEG8-NHS ester | CAS 2183440-34-6

Methyltetrazine-PEG8-NHS ester is a PEGylated NHS ester conjugate that couples a methyltetrazine click handle to primary amines on biomolecules and surfaces. As a tetrazine-based click chemistry reagent, it is designed for bioorthogonal conjugation workflows that commonly pair with trans-cyclooctene (TCO) reagents for rapid, strain-promoted inverse-electron-demand Diels–Alder ligation. The extended PEG8 spacer and NHS ester enable efficient targeting of amine-bearing targets such as proteins, peptides, and polymeric carriers, making it a widely used intermediate for building modular imaging probes, affinity reagents, and multicomponent chemical biology tools.

1. Protein Labeling For Imaging

Methyltetrazine-PEG8-NHS ester is used to functionalize amine-containing proteins with a tetrazine handle for subsequent click conjugation to TCO-modified imaging reporters. The NHS ester chemistry supports straightforward attachment to lysine residues under standard bioconjugation conditions, while the PEG8 spacer helps maintain accessibility of the tetrazine for downstream ligation. This makes the reagent a common choice for preparing modular protein-based probes used in fluorescence, affinity imaging, and other labeling workflows where a clean secondary conjugation step is advantageous.

2. Antibody And Ligand Conjugates

Methyltetrazine-PEG8-NHS ester is frequently applied in antibody and targeting ligand bioconjugation to introduce tetrazine functionality onto IgG, antibody fragments, and engineered binding proteins. By installing the tetrazine moiety through NHS-mediated coupling, researchers can generate Tz-functional affinity reagents that are later combined with TCO-bearing payloads in a controlled, modular manner. The PEG8 linker is particularly relevant when maintaining binding-site accessibility and reducing steric effects is important for multistep construct assembly.

3. Surface Functionalization Of Biomaterials

Methyltetrazine-PEG8-NHS ester supports the preparation of tetrazine-functional surfaces and biomaterial interfaces by reacting with amine groups present on coatings, porous scaffolds, and amine-derivatized polymers. This application is widely used in materials science and chemical biology to create clickable platforms for immobilizing TCO-tagged ligands, nanoparticles, or reporter molecules. The PEG8 spacer improves the presentation of the tetrazine handle at the interface, which can be critical for achieving efficient downstream conjugation and for enabling repeatable construction of multi-component surface assemblies.

4. Nanoparticle And Polymer Conjugation

Methyltetrazine-PEG8-NHS ester is used to incorporate tetrazine handles into nanoparticle formulations and polymer conjugates that contain accessible primary amines. Conjugation via the NHS ester allows researchers to tune the density of reactive tetrazine groups on carriers such as PEGylated nanoparticles, polymeric micelles, and functionalized colloids, enabling subsequent coupling to TCO-functional payloads. This approach is commonly adopted in research and industrial R&D settings to build modular multicomponent reagents for assay development, reagent optimization, and platform-based labeling strategies.