Propargyl-PEG6-thiol is widely used in bioconjugation and surface modification due to its reactive functional groups. The thiol group allows for strong covalent bonding with gold surfaces or other thiol-reactive materials, making it valuable in creating self-assembled monolayers (SAMs) for biosensors and nanotechnology applications. The propargyl group enables click chemistry, particularly copper-catalyzed azide-alkyne cycloaddition (CuAAC), which is essential for attaching biomolecules like peptides, proteins, or nucleic acids in a controlled and efficient manner. This compound is also utilized in drug delivery systems, where it helps in designing targeted and functionalized carriers. Its PEG spacer enhances solubility and reduces immunogenicity, making it suitable for biomedical and pharmaceutical research.