Azide-PEG12-alcohol（Cat No.:I015803）is a heterobifunctional polyethylene glycol reagent designed for modular conjugation and functionalization. It features a terminal azide group for copper-catalyzed or strain-promoted click chemistry with alkynes, and a hydroxyl group that serves as a versatile handle for further derivatization or coupling reactions. The long PEG12 spacer imparts excellent hydrophilicity, flexibility, and solubility, while minimizing steric hindrance and improving biomolecular accessibility. This reagent is widely applied in chemical biology, drug delivery, biomaterials, and proteomics, enabling controlled labeling, surface modification, and assembly of multifunctional molecular architectures.