Bis-PEG7-NHS ester is widely used in bioconjugation and crosslinking applications due to its reactive NHS ester groups and PEG spacer. It is commonly employed to link biomolecules, such as proteins, peptides, or antibodies, to other molecules or surfaces, enhancing solubility and reducing immunogenicity. The PEG spacer provides flexibility and improves stability in aqueous environments. This compound is particularly useful in drug delivery systems, where it helps create targeted therapeutics by conjugating drugs to carriers or antibodies. Additionally, it is utilized in the development of diagnostic assays and biosensors, where it facilitates the immobilization of biomolecules onto solid supports. Its water-soluble nature and biocompatibility make it a valuable tool in biomedical research and therapeutic applications.