The Acetylene-PEG4-biotin conjugate is widely used in bioconjugation and biochemical research. It serves as a valuable tool for labeling biomolecules, particularly proteins and nucleic acids, due to its biotin moiety, which enables strong binding with avidin or streptavidin. This property makes it essential in applications like pull-down assays, affinity purification, and detection systems such as ELISA and Western blotting. The PEG4 spacer enhances solubility and reduces steric hindrance, improving the efficiency of biotinylation processes. Additionally, the acetylene group allows for click chemistry reactions, facilitating the attachment of various probes or tags for imaging, diagnostics, and targeted drug delivery studies. Its versatility makes it a key reagent in proteomics, molecular biology, and drug development research.