Rebeads® NHS Magnetic Beads

Rebeads® NHS magnetic beads are microspheres modified with N-Hydroxysuccinimide (NHS). The NHS groups can react with amino-containing biomolecules (especially primary amines), such as proteins, antibodies, enzymes, polypeptides and nucleic acids, to form stable peptide bonds and achieve covalent coupling. They are widely used in affinity purification as well as the analytical detection of antibodies, antigens and other biomolecules.

1. Simple Operation: No pre-activation required; capable of direct covalent coupling with biological ligands.
2. High Efficiency: The coupling efficiency and binding capacity of biological ligands are much higher than those of carboxyl magnetic beads.
3. Fast Reaction: Coupling of various primary amine-containing biomolecular ligands can be completed within 1–2 hours.
4. Mild Conditions: Coupling can be performed at room temperature or 4℃, with a applicable pH range of 4~10 for the reaction system.
5. High Stability: Forms stable amide bonds to prevent ligand shedding.

This product can covalently couple all primary amine-group-containing substances such as proteins, antibodies and nucleic acids. It is widely applied in the separation and purification of proteins/antibodies, as well as immunoassay-related experimental techniques.

Work Flow

Coupling test of anti-AFM1 monoclonal antibody with NHS magnetic beads (quantified by Bradford protein assay)

1. Coupling Test of AFM1 Monoclonal Antibody with NHS Magnetic Beads (Determined by Bradford Protein Quantification Assay)

   AFM1 Monoclonal Antibody Dosage (μg)	Coupling Amount (μg)	Coupling Efficiency (%)
   5.00	4.67	93.40
   10.00	9.54	95.40
   20.00	19.27	96.35
   30.00	27.32	91.07
   40.00	34.53	86.33

Magnetic bead dosage: 100 μL; Coupling system: 1 mL Coupling Buffer.

With the increase of antibody concentration, the amount of antibody coupled to magnetic beads rises, while the coupling efficiency decreases.

1. Prior to use, thoroughly shake the product to maintain a uniform suspension of magnetic beads.
2. Do not centrifuge, dry or freeze the magnetic beads; such operations may cause bead aggregation and reduce binding activity.
3. NHS groups are prone to hydrolysis and sensitive to humidity. Tightly cap the bottle immediately after use, seal with parafilm, and store at -20 °C for long-term preservation.
4. Protein stabilizers such as BSA and gelatin can inhibit the binding between antibodies and magnetic beads. Therefore, ensure that the antibody storage system contains no primary amine-containing protein stabilizers during antibody coupling.
5. Substances containing primary amines in the buffer will inhibit protein coupling onto the bead surface. Dialysis and desalting are recommended to remove primary amine contaminants.