Description

Mono-Methyl Polyethylene Glycol 5'000 2-Maleimidoethyl Ether is a heterobifunctional PEG derivative featuring a reactive maleimide group at one terminus and a methoxy group at the other. This compound is essential for creating stable, site-specific conjugates in biopharmaceutical development, as the maleimide group selectively reacts with thiol groups under mild conditions. It is a critical reagent for researchers and manufacturers in the fields of bioconjugation, antibody-drug conjugate (ADC) development, and advanced drug delivery systems.

Application

• Antibody-Drug Conjugate (ADC) Linker: Site-specific conjugation of cytotoxic payloads to monoclonal antibodies via cysteine residues.
• PEGylation of Proteins and Peptides: Modification of therapeutic biomolecules to enhance solubility, reduce immunogenicity, and prolong circulation half-life.
• Surface Functionalization: Crafting biofunctional surfaces for biosensors, diagnostic assays, and biomaterials by attaching thiol-containing ligands.
• Cross-linking Agent: Creating stable bridges between molecules containing thiol and amine groups in controlled reaction sequences.
• Nanoparticle and Liposome Modification: Functionalizing drug delivery carriers for targeted therapy and improved pharmacokinetics.
• Diagnostic Reagent Synthesis: Conjugating enzymes, dyes, or other detection molecules to antibodies or other targeting moieties.

Basic Information

Product Name	Mono-Methyl Polyethylene Glycol 5'000 2-Maleimidoethyl Ether
CAS No.	99126-64-4
Molecular Formula	C2n+6H4n+12NOn+3 (n~113) / (C2H4O)nCH3O-(CH2)2-Maleimide
Molecular Weight	~5,000 Da (nominal)
Synonyms	mPEG-Maleimide (MW 5000); mPEG-MAL 5K; Methoxy PEG Maleimide (5000); Poly(ethylene glycol) methyl ether maleimide; α-Methyl-ω-maleimido poly(ethylene glycol); PEG-OMe Maleimide; 2,5-Dioxo-1-pyrrolidinyl ester of methoxy-PEG-propionic acid; N-(Methoxy poly(ethylene glycol))-3-maleimidopropionamide
EINECS	Contact for details

Quality Control

Our Mono-Methyl Polyethylene Glycol 5'000 2-Maleimidoethyl Ether is manufactured under strict quality management systems. Each batch is characterized and tested to ensure high purity, precise molecular weight distribution, and functional group integrity. Certificates of Analysis (COA) are provided, detailing key parameters such as assay, maleimide substitution, polydispersity, and residual solvent content. We support development and cGMP-grade requirements for pharmaceutical applications.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C or as indicated on the label. This material is hygroscopic (moisture-sensitive). Under inert atmosphere (e.g., argon or nitrogen) is recommended for long-term storage to maintain optimal reactivity. Allow the sealed vial to equilibrate to room temperature before opening to prevent moisture condensation.

Specification

Item	Specification
Appearance	White to off-white waxy solid or powder
Identification (IR)	Conforms to structure
Nominal Molecular Weight	5,000 Da
Maleimide Substitution	> 95%
Assay (HPLC)	> 98.0%
Polydispersity Index (PDI)	≤ 1.05
Methoxy Substitution	> 95%
Water Content (KF)	< 1.0%
Residual Solvent (GC)	Meets ICH guidelines

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.