Description

Bis-Mal-Lysine-Peg4-Acid is a heterobifunctional, amine-to-sulfhydryl crosslinking reagent featuring a maleimide group, a lysine core, and a tetraethylene glycol (PEG4) spacer terminated with a carboxylic acid. This molecular architecture is critical for creating stable, site-specific conjugates while improving solubility and reducing immunogenicity. It is an essential building block for researchers and manufacturers developing advanced biotherapeutics, including antibody-drug conjugates (ADCs), protein-protein conjugates, and peptide-drug conjugates.

Application

• Antibody-Drug Conjugate (ADC) Linker: Site-specific conjugation of cytotoxic payloads to cysteine residues on monoclonal antibodies via the maleimide group.
• Protein & Peptide Modification: Functionalization of proteins, enzymes, or peptides through amine groups (using the acid) for subsequent thiol-based coupling.
• Biomolecule Immobilization: Covalent attachment of proteins or peptides to solid surfaces (e.g., biosensors, microarray chips) via the carboxylic acid terminus.
• PEGylation Reagent: Introduction of a discrete, hydrophilic PEG4 spacer to biomolecules to enhance pharmacokinetic properties.
• Diagnostic Probe Synthesis: Construction of fluorescent or radioactive diagnostic probes by conjugating targeting ligands to reporter molecules.
• Hydrogel & Biomaterial Crosslinking: Creating tunable, biocompatible networks for drug delivery or tissue engineering applications.

Basic Information

Product Name	Bis-Mal-Lysine-Peg4-Acid
CAS No.	1426164-52-4
Molecular Formula	C31H48N4O14
Molecular Weight	700.74 g/mol
Synonyms	Bis-Maleimide-PEG4-Lysine-Acid; Nα,Nε-Bis(maleimido-PEG4-carbonyl)-L-lysine; Lys(Nε-MAL-PEG4-CO)-MAL-PEG4-COOH; Maleimide-PEG4-Lys(Maleimide-PEG4)-OH; Heterobifunctional PEG Crosslinker, Maleimide and Acid; BM(PEG)4-Lys-COOH; (2,5-Dioxo-2,5-dihydro-1H-pyrrol-1-yl) 17-((2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)oxy)-4,7,10,13-tetraoxo-16-oxa-3,6,9,12-tetraazaheptadecan-1-oate
EINECS	Contact for details

Quality Control

Our Bis-Mal-Lysine-Peg4-Acid is manufactured under strict quality management systems. Each batch undergoes rigorous analytical testing, including HPLC for purity, NMR and MS for structural confirmation, and functional group analysis to ensure consistent performance. A comprehensive Certificate of Analysis (COA) detailing identity, purity, and assay is provided with every shipment to support your research and regulatory documentation needs.

Storage

Preserve in a tightly closed container, protected from light. Store desiccated at -20°C or below under an inert atmosphere. This product is hygroscopic (moisture-sensitive) and the maleimide group is susceptible to hydrolysis. Allow the vial to equilibrate to room temperature in a desiccator before opening to minimize moisture uptake.

Specification

Item	Specification
Appearance	White to off-white solid
Identification (HPLC)	Conforms to reference standard
Identification (MS)	Conforms to structure (M+H+ or M+Na+)
Purity (HPLC)	≥ 95%
Assay	≥ 90% (Functional group titration)
Water Content (KF)	≤ 1.0%
Solubility	Soluble in DMSO, DMF, acetonitrile

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