DSPE-PEG4-DBCO is an amphiphilic conjugate consisting of a DSPE (1,2-distearoyl-sn-glycero-3-phosphoethanolamine) phospholipid, a PEG4 linker, and a DBCO (dibenzocyclooctyne) moiety. It is widely used in bioconjugation and copper-free click chemistry due to the strained alkyne in DBCO, enabling rapid and efficient strain-promoted azide-alkyne cycloaddition (SPAAC) reactions with azide-containing molecules without catalysts. The PEG4 spacer improves water solubility, flexibility, and reduces steric hindrance, while the DSPE lipid allows integration into lipid bilayers, liposomes, micelles, or cell membranes. This makes it ideal for functionalizing lipid-based nanoparticles, modifying biomolecules such as proteins, peptides, antibodies, and nucleic acids, and enabling targeted delivery in complex biological environments. It is particularly valuable in drug delivery systems for attaching therapeutic payloads to nanocarriers or cells, as well as in the development of biosensors, imaging probes, and diagnostic tools for precise biomolecule labeling and detection in research, biotechnology, and clinical applications. Its biocompatibility, stability, and versatility support advanced pharmaceutical and nanotechnological innovations.