Documents & Support

Dynabeads magnetic beads M-280 Tosylactivated allows direct covalent binding to primary amino or sulfhydryl groups in proteins and peptides at high pH and temperature.
Dynabeads magnetic beads M-270 Epoxy allows direct covalent binding to primary amino and sulfhydryl groups in proteins and peptides at neutral pH and a wide temperature range.
Dynabeads magnetic beads M-270 Amine allows direct covalent binding through reductive amination of aldehydes, or use of bi-functional NH2-reactive cross-linkers.
Dynabeads magnetic beads M-270 Carboxylic Acid and MyOne Carboxylic Acid allows covalent amide formation with primary amino groups in proteins and peptides.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Was this answer helpful?

This depends on the nature of the specific ligand to be immobilized and the desired downstream application.

The most frequently used surface activated Dynabeads magnetic beads for protein isolation are the Dynabeads magnetic beads M-280 Tosylactivated. Dynabeads magnetic beads M-280 Tosylactivated are hydrophobic, while the other surface activated beads (Dynabeads magnetic beads M-270 Epoxy, Dynabeads magnetic beads M-270 Amine and Dynabeads magnetic beads M-270 Carboxylic acid and Dynabeads magnetic beads MyOne Carboxylic acid) are all hydrophilic. Dynabeads magnetic beads M-280 Tosylactivated are easy to handle and ideal for covalent binding of antibodies for immunoprecipitation. Other ligands could also be covalently bound to these beads, but they have to tolerate conditions like neutral to high pH and high temperatures (required for covalent bond formation).

Dynabeads magnetic beads M-270 Epoxy is used when the ligand to be immobilized needs to be treated gently and will not tolerate harsh binding conditions like high temperature or pH. Proteins/peptides (other than antibodies) and enzymes are often coupled onto these beads.

Dynabeads magnetic beads M-270 Amine is often used in combination with cross-linkers to create specific surface groups on the beads. Hetro-bifunctional cross-linkers with an amine binding NHS group at one end and another chemical group of your choice at the other end are most frequently used. For example, Dynabeads magnetic beads M-270 Amine can be coated with a hetero-bifunctional cross-linker containing a NHS group at one end and maleimide at the other end to create Dynabeads magnetic beads with a maleimide surface. Since maleimide reacts specifically with sulfhydryl groups, these modified Dynabeads magnetic beads can be used for applications where binding of sulfhydryl groups are desired. Dynabeads magnetic beads M-270 Amine may also be used for direct ligand coupling via aldehyde or ketone groups by Schiff base (imine) formation and reductive amination. In addition carboxylic acid groups on a ligand can be activated with cabodiimide, which results in a direct amide bond formation between the beads and the ligand. Alternatively, a cross-linker may be introduced to the ligand. After activation of the ligand with cross-linker, the free end on the cross-linker has to be amine reactive.

Dynabeads magnetic beads M-270 Carboxylic Acid and Dynabeads magnetic beads MyOne Carboxylic Acid can also be used for immobilizing proteins. The carboxylic acid groups on these beads need to be activated (with carbodiimide) before coupling. The negative surface of these beads may attract positively charged proteins and cause nonspecific binding. This needs to be considered if the these beads are going to be used for immunoprecipitation.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Was this answer helpful?

SulfoLink Coupling Resin is iodoacetyl-activated agarose that reacts with reduced thiols to form a stable thioether linkage. CarboxyLink Coupling Resin is an amine-derivatized agarose that utilizes the carbodiimide crosslinker, EDC to conjugate the carbon of carboxylic acid to the nitrogen of the immobilized primary amine (hydrazide) to form a permanent amide bond.

Find additional tips, troubleshooting help, and resources within our Protein Purification and Isolation Support Center.

Was this answer helpful?

This depends on the nature of the specific ligand to be immobilized and the desired downstream application.

-The most frequently used surface-activated Dynabeads magnetic beads for protein isolation are the Tosyl-activated Dynabeads magnetic beads M-280. These beads are hydrophobic, easy to handle and ideal for covalent binding of antibodies for immunoprecipitation. Other ligands could also be covalently bound to these beads, but they have to tolerate conditions like neutral to high pH and high temperatures (required for covalent bond formation).
-Dynabeads magnetic beads M-270 Epoxy are used when the ligand to be immobilized needs to be treated gently and will not tolerate harsh binding conditions like high temperature or pH. Proteins/peptides (other than antibodies) and enzymes are often coupled onto these beads.
-Dynabeads magnetic beads M-270 Amine is often used in combination with crosslinkers to create specific surface groups on the beads. Hetro-bifunctional crosslinkers with an amine-reactive NHS group at one end and another chemical group of your choice at the other end are most frequently used. For example, Dynabeads magnetic beads M-270 Amine can be reacted with a hetero-bifunctional crosslinker containing a NHS group at one end and maleimide at the other end to create Dynabeads magnetic beads with a maleimide surface. Since maleimide reacts specifically with sulfhydryl groups, these modified Dynabeads magnetic beads can be used for applications where binding of sulfhydryl groups are desired. Dynabeads magnetic beads M-270 Amine may also be used for direct ligand coupling via aldehyde or ketone groups by Schiff base (imine) formation and reductive amination. In addition carboxylic acid groups on a ligand can be activated with a carbodiimide like EDC, which results in a direct amide bond formation between the beads and the ligand. Alternatively, a crosslinker may be introduced to the ligand. After activation of the ligand with crosslinker, the free end on the crosslinker has to be amine reactive.
-Dynabeads magnetic beads M-270 Carboxylic Acid and Dynabeads magnetic beads MyOne Carboxylic Acid can also be used for immobilizing proteins. The carboxylic acid groups on these beads need to be activated with a carbodiimide before coupling. The negatively-charged surface of these beads may attract positively charged proteins and cause nonspecific binding. This needs to be considered if these beads are going to be used for immunoprecipitation.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Was this answer helpful?

CarboxyLink can be used to immobilize any protein or peptide via the C-terminus or aspartic or glutamic acid residues. Diaminodiproylamine (DADPA) is immobilized onto an agarose support. The carbodiimide crosslinker, EDC facilitates the formation of an amide bond between the carbon of the carboxylic acid and the nitrogen on the terminal amine of DADPA. This support is compatible with 50% organic solvent to improve immobilization of hydrophobic peptides.

Find additional tips, troubleshooting help, and resources within our Protein Purification and Isolation Support Center.

Was this answer helpful?

These compounds are used in conjunction with the crosslinker EDC (Cat. No. 22980, 22981, 77149, A35391) to synthesize amine-reactive labeling reagents, crosslinkers and conjugation compounds. Any compound containing a carboxylic acid (-COOH), such as a protein, or biotin or peptide, can be activated with NHS or Sulfo-NHS to form an NHS ester that will spontaneously react to form covalent amide linkages with proteins and other molecules that contain primary amines (-NH2).

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Was this answer helpful?

Dynabeads M-280 Tosyl activated magnetic beads allow direct covalent binding to primary amino or sulfhydryl groups in proteins and peptides at high pH and high temperature.
-Dynabeads M-270 Epoxy magnetic beads allow direct covalent binding to primary amino and sulfhydryl groups in proteins and peptides at neutral pH and across a wide temperature range.
-Dynabeads M-270 Amine magnetic beads allow direct covalent binding through reductive amination of aldehydes, or the use of bifunctional amine-reactive crosslinkers.
-Dynabeads M-270 and MyOne Carboxylic Acid magnetic beads allow covalent amide formation with primary amino groups in proteins and peptides.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.

Was this answer helpful?