SileksMag-NH₂, amino covered magnetic particles, 1 mL

Amino magnetic particles are supplied as an aqueous suspension ready for use.

Magnetic particles with an amino group make it possible to covalently immobilize antibodies or protein. The initial particles have high hydrophilic shell and low nonspecific sorption of proteins on their surface. For the possibility of immobilization of proteins, the particles are modified and have active NH₂ groups on the surface.

Magnetic particles with an amino group are designed to carry out the procedure of covalent binding of a protein on its surface. As a result of this procedure, you get the opportunity to:
- immunomagnetic isolation of unique cells or proteins from biological fluids,
- increasing the sensitivity of immunological studies by concentrating a specific material

Advantages of covalent bonding over passive adsorption
Covalent binding allows you to bind 20-40% more protein on the surface than with passive adsorption
Covalent bonding is easy to standardize and unify, producing particles with a defined level of coverage
Covalently linked proteins are much more stable. So, after 1 hour at 56 ° C, the amount of IgG on covalently attached particles remains practically unchanged at about 100%, while on particles with passive adsorption only 50-70%
In the case of small proteins, only covalent attachment can hold them on the surface.
When a protein is covalently bound, it is possible to create sufficiently stringent conditions to reduce the nonspecific interaction of the bound protein with other proteins.

The amount of immobilized protein
The proposed particles can bind 60 μg of bovine serum albumin (BSA, 65 kDa) or 50 μg of IgG (150 kDa) per 1 mg of particles. When binding proteins other than those indicated, the size of the protein should be taken into account: smaller proteins can be bound in larger quantities, larger ones in smaller quantities. As the immobilized protein binds to the surface, the rate and efficiency of binding decreases. This problem can be solved either by increasing the immobilization time, or by creating an excess of protein greater than the amount that can be immobilized by the particles. Of course, in the case of expensive immobilizable materials, the latter option is undesirable.

Influence of temperature and time on the immobilization process
Temperature has little effect on the covalent immobilization process. In the event that the immobilized protein is thermolabile, the immobilization reaction can be carried out at +10 °C. An increase in the duration of the immobilization process itself from 2 hours to 5 hours increases the amount of immobilized protein by approximately 10-15%.