Maleimide-NH-PEG-PFP Ester

Mal-NH-PEGn-CH₂CH₂COOPFP Ester is a heterotrifunctional reagent designed for efficient multi-step bioconjugation, enabling sequential thiol-specific maleimide coupling, amine-reactive PFP ester binding, and further functionalization via the intermediate amine group. Its key advantages include enhanced hydrolysis resistance compared to NHS esters, tunable spacer length (n), and high reactivity with amines under mild conditions, though the PFP ester may require synthesis in anhydrous environments and the maleimide group remains sensitive to hydrolysis and retro-Michael reactions.