HO-PEG-NH2 is widely used in bioconjugation and drug delivery systems due to its dual functional groups. The hydroxyl group allows for further modification, while the amine group enables covalent attachment to various molecules, such as proteins, peptides, or drugs. It is particularly valuable in creating PEGylated therapeutics, enhancing solubility, stability, and circulation time of drugs in the body. Additionally, it serves as a linker in the synthesis of hydrogels and nanoparticles, contributing to controlled release and targeted delivery applications. Its biocompatibility and water solubility make it a key component in biomedical research and pharmaceutical development.