Product Description of Methyl-PEG9-acid (Methyl-Polyethylene Glycol 9-Acid)
Methyl-PEG9-acid has the molecular formula C₂₂H₄₄O₁₂. It is composed of a nine-unit polyethylene glycol (PEG) chain terminated with a methoxy group and an end carboxylic acid group (-COOH), combining hydrophilicity and reactivity. Its production is achieved through the ring-opening polymerization of ethylene oxide units, with the carboxylic acid terminal group introduced via chemical modification, achieving a purity of over 98%. As a bifunctional PEG derivative, its carboxylic acid end can form amide or ester bonds with amines and hydroxyl groups. It is widely used in non-degradable linkers for antibody-drug conjugates (ADCs), flexible spacers for PROTAC molecules, and hydrophilic surface modification of nanomaterials, significantly enhancing biocompatibility and stability.