Azido-PEG(4)-Val-Cit-PAB-PNP

Azido-PEG(4)-Val-Cit-PAB-PNP is a highly functional ADC linker designed for advanced antibody-drug conjugate (ADC) construction and precise bioconjugation applications. Featuring an azide group for bioorthogonal click chemistry, a PEG4 spacer, and a Val-Cit-PAB protease-cleavable sequence, along with a PNP reactive ester, this linker allows site-specific attachment of ADC cytotoxins to antibodies. The PEG4 spacer improves solubility, reduces steric hindrance, and enhances flexibility, facilitating efficient ADC linker design. Azido-PEG(4)-Val-Cit-PAB-PNP supports controlled intracellular payload release while maintaining antibody structure and biological function.

In payload conjugation applications, Azido-PEG(4)-Val-Cit-PAB-PNP is compatible with a wide range of ADC cytotoxins, including microtubule inhibitors and DNA-targeting agents. The PNP ester enables rapid and reproducible coupling to nucleophilic sites on antibodies, while the azide group provides bioorthogonal conjugation options for modular ADC assembly. The Val-Cit-PAB cleavable sequence ensures selective intracellular release by lysosomal proteases, and the PEG4 spacer enhances solubility and pharmacokinetics. Researchers can use this linker to construct homogeneous, stable ADCs with controlled payload release profiles and enhanced therapeutic performance.

From an application perspective, Azido-PEG(4)-Val-Cit-PAB-PNP is extensively applied in oncology-focused ADC research, targeted drug delivery studies, and protease-sensitive bioconjugation strategies. Its unique combination of azide reactivity, PNP ester chemistry, PEG4 spacer, and cleavable Val-Cit-PAB sequence enables efficient, site-specific conjugation while preserving antibody integrity. Incorporating this linker into ADC designs allows the creation of adaptable, stable linker-payload conjugates that achieve precise tumor targeting and optimized intracellular payload release for enhanced therapeutic outcomes.