Biotin methylester is widely used in biochemical research as a labeling reagent. It is particularly valuable for tagging proteins, nucleic acids, and other biomolecules due to its ability to bind strongly with avidin or streptavidin. This property makes it essential in techniques like ELISA, immunohistochemistry, and Western blotting for detection and purification purposes. Additionally, it is employed in the study of biotin-dependent enzymes and metabolic pathways, helping to elucidate their mechanisms and functions. Its stability and specificity also make it a useful tool in drug discovery and diagnostic assays.