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Cat. No.: CMB1k-5 (for 5ml)

Cat. No.: CMB1k-50 (for 50ml)

Cat. No.: CMB1k-200 (for 200ml)

Description

Carboxyl Magnetic Beads, also known as carboxylated magnetic beads, carboxyl-derivatized magnetic beads, and carboxyl-derivatized microspheres, are a type of high-quality submicron magnetite microspheres (Fe3O4 microspheres) coated with carboxyl groups (-COOH). They can be quickly, efficiently, sensitively, and specifically covalently coupled with biomolecules such as polypeptides, proteins, antibodies, and oligonucleotides under the action of special chemical reagents (such as EDC and NHS). They can be subsequently used for immunoprecipitation (IP), cell sorting, DNA-protein interaction, etc., and are important carrier tools in medical and life science research.

Magnetic separation is a method that uses the force of an external magnetic field on magnetic materials to combine and separate biomolecules and cells while retaining their biological activity. It has the advantages of large adsorption capacity, fast separation speed, high efficiency, reusability, and simple operation [1,2]. Conventional magnetite microspheres, as commonly used magnetic materials, have high magnetic responsiveness and excellent biocompatibility, but they are not surface-modified, unstable, and easy to aggregate and precipitate themselves. Common functionalized magnetic beads include carboxyl magnetic beads and amino magnetic beads. Carboxyl or amino groups are coated on the shell structure of the magnetic beads to reduce the aggregation and precipitation of the magnetic beads themselves. Carboxyl magnetic beads are acidic and are usually activated with EDC/NHS in acidic buffers, while amino magnetic beads are basic and are usually activated with glutaraldehyde in alkaline buffers.

This series of carboxyl magnetic bead products is an aqueous suspension of superparamagnetic magnetite microspheres coated with carboxyl groups. The advanced technology used makes the magnetic beads perfectly combined with high molecular materials or citric acid, which is a new type of functionalized magnetic microsphere. Compared with traditional magnetic beads, this series of carboxyl magnetic bead products have many advantages, such as superparamagnetism, high carboxyl density, fast magnetic response, good dispersion, fast separation speed, high recovery rate, and strong specificity. They can be conveniently and efficiently combined with various biomolecules (polypeptides, proteins, antibodies, etc.) with high loading capacity, and can also be used as a good basic material for subsequent encapsulation, adsorption, chemical modification, etc. At the same time, the polymer/citric acid shell of this series of carboxyl magnetic bead products can protect the target molecules combined with the magnetic beads from the negative effects of iron ions.

The basic principle of covalent coupling of carboxyl magnetic beads (carboxyl magnetic beads) with biomolecules such as proteins and antibodies is as follows. Bioconjugation is the process of linking biomolecules together through covalent chemical bonds. Bioconjugation reagents contain reactive end groups that can react with specific functional groups (such as primary amines and thiol groups).

Primary amine (-NH2) is present at the N-terminus of each polypeptide chain and in the side chains of lysine residues. Since the primary amine carries a positive charge, it is usually located on the outer surface of the protein, making it more accessible for conjugation without changing the protein structure. Carbodiimides (EDC) can react with carboxyl groups to form an active O-acylisourea intermediate, which is then attacked and displaced by the nucleophilic group of the primary amine, resulting in the cross-linking of carboxyl and amino groups. However, the intermediate is unstable and easily hydrolyzed, so N-hydroxysuccinimide (NHS) or its water-soluble analog (Sulfo-NHS) is often introduced into the reaction system to improve the efficiency. EDC reacts with NHS to form a stable NHS ester (NHS esters), which then reacts with the primary amine under mild alkaline conditions to form a stable amide bond, achieving the purpose of biomolecule conjugation.

Features

• This series of carboxyl magnetic bead products has strong specificity, high ligand density, and high binding capacity. Compared with most similar products at home and abroad, this series of carboxyl magnetic bead products has high carboxyl density and strong reaction specificity for biomolecules with primary amines.
• This series of carboxyl magnetic bead products is available in three particle sizes: 200nm, 500nm and 1µm. Each milliliter of magnetic bead suspension contains about 10mg of magnetic beads, which can react and bind to no less than 0.6mg of IgG antibody. The specific maximum binding capacity is related to the molecular weight of the biomolecule.
• This series of carboxyl magnetic bead products has a fast reaction rate with biomolecules. The high carboxyl density of this series of carboxyl magnetic bead products allows the activated carboxyl magnetic beads to quickly couple with biomolecules containing primary amines, saving operation time.
• This series of carboxyl magnetic bead products has good dispersibility and resuspendability. This series of carboxyl magnetic bead products has been modified with high molecular materials to avoid the aggregation of magnetic beads, so that the magnetic beads have good monodispersity and stable physicochemical properties. The magnetic beads have good reproducibility and convenience when performing biomolecule coupling reactions.

Storage

Store at 4°C for two years.

Note

• The magnetic beads with appropriate functional groups and particle sizes should be selected according to the characteristics of the biomolecule.
• This series of carboxyl magnetic bead products are not activated and need to be activated according to the instructions before they can be used for coupling with proteins, antibodies and other biomolecules.
• The pH of this series of carboxyl magnetic bead products should be maintained between 6 and 8. Avoid high-speed centrifugation and drying. Do not place the magnetic beads in a magnetic field for a long time, otherwise it may cause the magnetic beads to aggregate.
• Before use, this series of carboxyl magnetic bead products should be resuspended properly and sufficiently, that is, invert several times to mix the magnetic beads evenly, and shake or sonicate vigorously to make the magnetic beads in a uniform suspension state.
• To ensure the best coupling effect, the coupling buffer should not contain Tris or other primary amine-containing solutions.
• If a vacuum pump or other instrument is used to aspirate the supernatant, pay attention to the suction strength of the vacuum pump to avoid excessive suction and absorbing accumulated magnetic beads.
• This product is limited to scientific research by professionals and cannot be used for clinical diagnosis or treatment. It cannot be used for food or medicine, and it cannot be stored in ordinary houses.
• For your safety and health, please wear a lab coat and disposable gloves when operating.

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Only for research and not intended for treatment of humans or animals

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