Used in bioconjugation and labeling applications, particularly in click chemistry reactions. It serves as a linker for attaching biomolecules like proteins, peptides, or antibodies to other entities, such as fluorescent dyes or drug molecules. The maleimide group reacts selectively with thiol groups, while the DBCO (dibenzocyclooctyne) enables strain-promoted azide-alkyne cycloaddition (SPAAC) for efficient conjugation without the need for catalysts. This makes it valuable in drug delivery systems, diagnostic assays, and research tools for studying molecular interactions. Its PEG4 spacer enhances solubility and reduces steric hindrance, improving reaction efficiency.