Description

n-Ethylmaleimide-Cysteine is a high-purity biochemical reagent designed for advanced research and industrial applications. This compound is a critical tool for studying protein structure and function, specifically through the selective modification of cysteine residues. It is essential for researchers and manufacturers in the fields of proteomics, enzymology, and bioconjugate chemistry who require reliable and specific thiol-reactive agents. The product is supplied under stringent quality control to ensure consistent performance in sensitive biochemical assays.

Application

• Protein Structure-Function Studies: Selective labeling and cross-linking of cysteine residues in proteins to investigate folding, activity, and interactions.
• Enzyme Inhibition Analysis: Used as an active site-directed irreversible inhibitor for thiol-dependent enzymes to elucidate catalytic mechanisms.
• Bioconjugation and Linker Chemistry: Serves as a key intermediate for synthesizing protein-drug conjugates, antibody-enzyme complexes, and other biomolecular constructs.
• Proteomics Research: Employed in mass spectrometry-based workflows for mapping protein thiols and studying redox states.
• Pharmaceutical Intermediate: Potential use in the development of targeted therapeutics that rely on covalent binding to specific protein targets.
• Biochemical Assay Development: A critical reagent for developing diagnostic kits and assays that depend on specific thiol modification.

Basic Information

Product Name	n-Ethylmaleimide-Cysteine
CAS No.	60218-98-6
Molecular Formula	C9H12N2O4S
Molecular Weight	244.27 g/mol
Synonyms	N-Ethylmaleimide L-Cysteine Adduct; L-Cysteine N-Ethylmaleimide; Cys-NEM; NEM-Cysteine; S-(N-Ethylsuccinimido)cysteine; 2-Amino-3-[(2,5-dioxo-1-ethylpyrrol-3-yl)sulfanyl]propanoic acid; N-Ethylmaleimide cysteine derivative
EINECS	Contact for details

Quality Control

Our n-Ethylmaleimide-Cysteine is manufactured under a quality management system and undergoes rigorous analytical testing to ensure it meets the high standards required for research and development. Each batch is characterized by techniques including HPLC, NMR, and mass spectrometry to confirm identity, purity, and stability. A comprehensive Certificate of Analysis (COA) detailing all test results is provided with every shipment to guarantee traceability and compliance with your project requirements.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at 2-8°C. The product is hygroscopic (moisture-sensitive) and should be handled under anhydrous conditions to maintain stability. Allow the container to reach room temperature before opening to prevent condensation.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to structure
Identification (NMR)	Conforms to structure
Purity (HPLC)	≥ 95.0%
Water Content (KF)	≤ 5.0%
Heavy Metals	≤ 20 ppm
Residual Solvents (GC)	Meets ICH guidelines

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