Thermo Scientific™ MBS (m-maleimidobenzoyl-N-hydroxysuccinimide ester)

Thermo Scientific™ Pierce MBS (m-maleimidobenzoyl-N-hydroxysuccinimide ester) is a heterobifunctional crosslinker designed to covalently link amine and sulfhydryl-containing biomolecules. It is widely used in bioconjugation, especially for creating enzyme immunoconjugates, antibody-drug conjugates, and protein-protein interactions.

Key Features & Benefits

• Heterobifunctional Crosslinker: Contains both NHS-ester and maleimide reactive groups.
• Specific Reactivity: Targets amine (-NH₂) groups on one end and sulfhydryl (-SH) groups on the other.
• Short Spacer Arm: 7.3 Å distance between reactive sites ensures efficient molecular linkage.
• Non-cleavable: Forms stable covalent bonds that are not disrupted by reducing conditions.
• Water-Insoluble: Requires pre-dissolution in organic solvents such as DMF (dimethylformamide) or DMSO (dimethyl sulfoxide) before use.
• High Reactivity & Efficiency: Optimized for bioconjugation applications.
• Compatible with Enzyme Labeling: Ideal for preparing enzyme-labeled antibodies and immunoconjugates.

Chemical Properties

• Molecular Weight: 314.25 g/mol
• Crosslinker Type: Heterobifunctional
• Cleavable: No
• Spacer Arm Length: 7.3 Å
• Water Solubility: No (soluble in DMF, DMSO)
• Format: Powder
• Storage Conditions: Store desiccated at 4°C

Applications

1. Protein and Antibody Conjugation:
   • Used in enzyme immunoassays (ELISA) to link enzymes such as horseradish peroxidase (HRP) or alkaline phosphatase (AP) to antibodies.
   • Essential for antibody-drug conjugates (ADCs) in targeted drug delivery.
2. Biomolecule Labeling:
   • Covalently links peptides, proteins, or nucleic acids to fluorescent dyes, biotin, or nanoparticles.
   • Facilitates fluorescence-based tracking of biomolecules.
3. Cell and Molecular Biology Research:
   • Crosslinks cell surface receptors to ligands, aiding in signal transduction studies.
   • Used in protein interaction studies to stabilize protein-protein complexes.
4. Drug Discovery & Pharmacology:
   • Plays a role in designing bi-specific antibodies and small-molecule conjugates.
   • Helps stabilize drug delivery vehicles like liposomes.
5. Nanotechnology and Biosensors:
   • Used in nanoparticle functionalization for biosensing applications.
   • Enhances biochip performance by immobilizing proteins or DNA onto solid supports.

Usage Guidelines

1. Dissolve in Organic Solvent: Since MBS is water-insoluble, dissolve it first in DMF or DMSO before introducing it to aqueous buffers.
2. Amine Conjugation First: The NHS-ester group reacts with primary amines at pH 7.2-8.5 to form stable amide bonds.
3. Sulfhydryl Conjugation Next: After reacting with the amine-containing molecule, the maleimide group selectively reacts with free thiol (-SH) groups at pH 6.5-7.5.
4. Storage & Handling: Store desiccated at 4°C to prevent hydrolysis and maintain reactivity.

Alternative Products & Related Crosslinkers

• Thermo Scientific™ Sulfo-MBS – Water-soluble alternative with similar properties.
• Thermo Scientific™ SMCC (Succinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate) – Another non-cleavable, heterobifunctional crosslinker with a cyclohexane spacer.
• Thermo Scientific™ DSP (Dithiobis(succinimidyl propionate)) – Cleavable crosslinker with a disulfide bridge.

Ordering Information

Thermo Scientific™ Pierce MBS is a powerful heterobifunctional crosslinker designed for bioconjugation, protein labeling, and molecular interactions. Its NHS-ester and maleimide groups ensure specific, efficient, and stable conjugation of proteins, peptides, antibodies, and nanoparticles for various biomedical, pharmaceutical, and nanotechnology applications.