4-Arm-PEG-Azide (MW 2000)

4-Arm-PEG-Azide (MW 2000) (4-Arm-PEG-N3 (MW 2000)) is a PEG derivative composed of a PEG unit and an azide group. It contains an azide group and can undergo copper-catalyzed azide-alkyne cycloaddition reaction (CuAAc) with molecules containing alkyne groups. It can also undergo ring strain-driven alkyne-azide cycloaddition reaction (SPAAC) with molecules containing DBCO or BCN groups.