Used in bioconjugation and drug delivery systems, CbzNH-PEG5-CH2COOH serves as a linker molecule with a carbobenzyloxy (Cbz)-protected amino group, polyethylene glycol (PEG5) spacer, and carboxylic acid terminus. The Cbz group can be deprotected to enable attachment of therapeutic agents or targeting moieties, while the PEG spacer enhances solubility and reduces immunogenicity. This makes it suitable for improving the pharmacokinetics of drugs. It is employed in the development of antibody-drug conjugates (ADCs) and other targeted therapies, ensuring precise delivery of drugs to specific cells or tissues. The carboxylic acid group allows for easy activation and conjugation with amines on biomolecules like proteins or antibodies, expanding its utility in biomedical research and therapeutic applications.