Ald-Ph-PEG-Azide is a versatile compound used in pharmaceutical research and development. It is classified as an aldehyde-terminated polyethylene glycol (PEG) molecule, containing a terminal azide group. The aldehyde and azide groups provide functional handles for further modification and conjugation to various biomolecules. The PEG moiety improves solubility, biocompatibility, and reduces immunogenicity of the resulting drug conjugates. The azide group enables the selective and efficient click chemistry-based conjugation of the drug molecule to various biomolecules, such as peptides, antibodies, or small molecules. Ald-Ph-PEG-Azide has become a popular tool for designing novel drug delivery systems, imaging agents, and therapeutics with improved efficacy and reduced side effects.