Mal-amido-PEG4-NHS ester

• CAT Number: I016719
• CAS Number: 756525-99-2
• Molecular Formula: C22H31N3O11
• Molecular Weight: 513.50
• Purity: ≥95%
• Synonyms: (2,5-dioxopyrrolidin-1-yl) 3-[2-[2-[2-[2-[3-(2,5-dioxopyrrol-1-yl)propanoylamino]ethoxy]ethoxy]ethoxy]ethoxy]propanoate
• InChI: InChI=1S/C22H31N3O11/c26-17(5-8-24-18(27)1-2-19(24)28)23-7-10-33-12-14-35-16-15-34-13-11-32-9-6-22(31)36-25-20(29)3-4-21(25)30/h1-2H,3-16H2,(H,23,26)
• InChIKey: XSRYGQJQNPJNKZ-UHFFFAOYSA-N
• SMILES: C1CC(=O)N(C1=O)OC(=O)CCOCCOCCOCCOCCNC(=O)CCN2C(=O)C=CC2=O

Mal-amido-PEG4-NHS ester(CAT: I016719) is a heterobifunctional PEG linker designed for efficient and selective bioconjugation. It contains a maleimide (Mal) group that reacts with sulfhydryl (–SH) groups on cysteine residues and an N-hydroxysuccinimide (NHS) ester that couples to primary amines (–NH₂) on proteins, peptides, or other biomolecules. The PEG4 spacer improves water solubility, reduces steric hindrance, and enhances flexibility in conjugates, making it highly useful for preparing antibody–drug conjugates (ADCs), protein labeling, surface modification, and biomaterial functionalization. Mal-amido-PEG4-NHS ester provides a versatile and reliable crosslinker for applications in chemical biology, bioconjugate chemistry, diagnostics, and therapeutic development.