Used as a heterobifunctional bioconjugation reagent, this compound features a maleimide group for selective reaction with thiol groups (–SH) in cysteine residues of proteins or peptides, and a biotin moiety that binds strongly to streptavidin or avidin. It enables the biotinylation of thiol-containing biomolecules for detection, purification, or immobilization in streptavidin-based systems.

The 3,6-dioxaoctane (PEG-like) spacer enhances aqueous solubility, provides flexibility, and reduces steric hindrance, improving the accessibility and binding efficiency of the conjugated molecules.

Commonly applied in immunoassays, targeted drug delivery, surface coating for diagnostic platforms, proteomics, and cell surface labeling, where site-specific conjugation is essential.