Amino-PEG9-amine is widely used in bioconjugation and nanotechnology due to its dual amine groups and polyethylene glycol (PEG) spacer. It serves as a linker molecule in drug delivery systems, enabling the attachment of therapeutic agents to targeting molecules like antibodies or peptides. This enhances the solubility, stability, and bioavailability of drugs while reducing immunogenicity. In surface modification, it is employed to functionalize nanoparticles, improving their biocompatibility and circulation time in biological systems. Additionally, it is utilized in the synthesis of hydrogels and biomaterials for tissue engineering, providing a flexible and hydrophilic environment for cell growth. Its role in crosslinking reactions also makes it valuable in creating advanced polymeric materials for various biomedical applications.