Biotin-PEG4-azide is a very useful biotinylation reagent that enable Click Chemistry reaction with alkyne, such as Propargyl, DBCO or BCN reagent to form a stable bond. PEG4 spacer increases aqueous solubility of the molecules conjugated to the biotin. It also helps to minimize steric hindrance involved with the binding to avidin molecules. Reagent grade, for research purpose. Please contact us for GMP-grade inquiries.