Mal-PFP ester is widely used in biochemical research for labeling and modifying biomolecules, particularly proteins and peptides. Its primary application lies in its ability to act as a reactive ester, facilitating the attachment of various functional groups to target molecules. This makes it valuable in the development of fluorescent probes, affinity tags, and other diagnostic tools. It is also employed in drug delivery systems to conjugate therapeutic agents with targeting molecules, enhancing specificity and efficacy. Additionally, Mal-PFP ester plays a role in crosslinking experiments, aiding in the study of protein interactions and structural analysis. Its versatility and reactivity make it a key reagent in bioconjugation chemistry.