Description Features and Benefits TFP-dPEG®4-biotinidase resistant biotin contains an amine reactive TFP ester and chemically modified biotin that is stable in the presence of biotinidase. Resistance to biotinidase cleavage of biotin is necessary in some biotechnology applications. The chemical modification to biotin imparts resistance to biotinidase cleavage without reducing the strength of biotin-avidin binding. The single molecular weight dPEG® spacer imparts water solubility, prevents aggregation and precipitation of labeled peptides and proteins, and reduces non-specific binding. Two different single molecular weight dPEG® spacers are available for precise spatial control between the modified biotin and the surface of the molecule to which it is conjugated. Legal Information Products Protected under U.S. Patents # 7,888,536 B2 dPEG is a registered trademark of Quanta BioDesign