THP-PEG9-OH is widely used in the field of bioconjugation and drug delivery due to its unique properties. The tetrahydropyran (THP) protecting group ensures stability during chemical reactions, while the polyethylene glycol (PEG) spacer enhances solubility and reduces immunogenicity. This compound is particularly valuable in the synthesis of prodrugs, where it serves as a linker to attach therapeutic agents, enabling controlled release and targeted delivery. Additionally, it is employed in the modification of peptides and proteins to improve their pharmacokinetics and bioavailability. Its application extends to the development of advanced materials, such as hydrogels and nanoparticles, where it contributes to enhanced biocompatibility and functionality.