Used in bioconjugation and labeling applications, particularly in click chemistry reactions. It serves as a linker molecule to attach biotinylated compounds to azide-functionalized targets, enabling detection or purification processes. Commonly employed in protein labeling, cellular imaging, and drug delivery systems. Its biotin moiety allows for strong binding to streptavidin or avidin, facilitating efficient isolation or visualization. The PEG2 spacer enhances solubility and reduces steric hindrance, improving reaction efficiency. Widely utilized in biochemical research, diagnostics, and biopharmaceutical development.