Chinese name

4-Maleimidebenzoic acid

English name

4-MBA; p-Maleimidobenzoic acid

CAS

5855-13-4

Molecular formula

C ₁₁ H ₇ NO ₄

Molecular weight

217.18

Major category

Segmentation

Description

Biomarker

Protein and Antibody Labeling

Fluorescent dyes, biotin, enzymes, or other reporter molecules are conjugated to proteins or antibodies bearing free thiol groups via their carboxyl moieties. First, the carboxyl group of 4‑MBA is activated with EDC/NHS to enable its reaction with the amino groups on the reporter molecule; subsequently, the resulting maleimide‑functionalized reporter can specifically bind to the thiol groups on the protein.

Peptide (protein) crosslinking, complicating spatial conformation

It is used to link a molecule containing an amino group (such as a peptide or protein) with another molecule bearing a thiol group, enabling the study of intermolecular interactions or the construction of complex biomolecular complexes.

Biosensor Preparation

In the construction of biosensors, it is used to immobilize biorecognition elements—such as antibodies or enzymes—on the sensor chip surface in a定向 manner, thereby preserving their biological activity.

Medicine

Antibody-Drug Conjugates (ADCs)

In the construction of ADCs, it can be used to conjugate cytotoxic drugs to monoclonal antibodies. Antibodies are typically rendered thiol‑bearing by reducing their interchain disulfide bonds, enabling efficient and specific coupling with maleimide groups.

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Material modification or functionalization

Maleimide-modified resin (via physical blending or chemical incorporation)

For example, bismaleimides are chemically modified with polyphenylene ether, aminoplasts, and other materials;

For example, copolymerization modification with allyl‑type compounds (allyl phenol oxides, allyl bisphenol A) and benzoxazine compounds.

Surface modification of materials by introducing maleimide groups.

Surface modification of amino-containing materials (such as amino-modified magnetic beads, chips, nanoparticles, etc.)