What reactive groups do you offer for your surface-activated Dynabeads magnetic beads?
We offer tosyl, epoxy, carboxylic acid and amine activated Dynabeads magnetic beads. Please see the link (https://tools.thermofisher.com/content/sfs/brochures/Surface_Activated_Dynabeads.PDF) for a comparison of the beads.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
What is the density of Dynabeads magnetic beads?
The density of Dynabeads magnetic beads is a challenging property to determine. The reason is that Dynabeads magnetic beads have a 17-37% magnetic iron oxide content in order to have a reasonable magnetic separation time, and the density of the iron oxide is about 4.9 g/cm3. Dynabeads magnetic beads are composite materials, being a mix of polymers and iron oxide, and there are very few polymers that have a density below 1.
The sedimentation rate depends on the bead diameter squared, so the sedimentation of a 1 µm bead is much slower than that of 2.8 µm. The effect of diameter on sedimentation rate is to some extent counteracted by the fact that smaller beads need to have a higher content of iron oxide for magnetic separation applications. Typically, our M-280 Dynabeads (diameter 2.8 µm) have a density of 1.4 g DS/cm3 (DS = dry substance), our M-270 Dynabeads (diameter 2.8 µm) and M-450 Dynabeads (diameter 4.5 µm) have a density of 1.6 g DS/cm3, and our MyOne Dynabeads (diameter 1 µm) have a density of 1.8 g DS/cm3.
Find additional tips, troubleshooting help, and resources within our Dynabeads Nucleic Acid Purification Support Center as well as our Dynabeads Cell Isolation and Expansion Support Center and Protein Immunoprecipitation (IP), Co-Immunoprecipitation (Co-IP), and Pulldown Support Center.
I am using surface-activated Dynabeads magnetic beads. When do I need to use a linker secondary antibody?
A linker antibody provides proper orientation of the target-specific primary antibody. Optimal orientation of the primary antibody is more important for reacting with larger organelles than for small organelles or membrane fractions. Different linkers can be used, but we recommend using an Fc-binding antibody, such as a monoclonal or polyclonal anti-mouse IgG. The linker antibody must be affinity purified and not contain stabilizers such as sugars or proteins that may bind to the Dynabeads magnetic beads. The specific primary antibody, if polyclonal, must be affinity purified in order to provide a high density of the specific antibody on the Dynabeads magentic beads surface.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
What is the definition of superparamagnetic, and what does this mean for my cell isolation application with Dynabeads magnetic beads?
Superparamagnetic means that the Dynabeads magnetic beads exhibit magnetic properties when placed within a magnetic field, but have no residual magnetism when removed from the magnetic field.
This means that your targeted cells, proteins, or nucleic acids are only subjected to magnetic forces during the time the beads are on the magnet. The beads do not aggregate, but remain evenly dispersed in suspension.
Find additional tips, troubleshooting help, and resources within our Dynabeads Cell Isolation and Expansion Support Center.
Are the antibodies on your Dynabeads magnetic beads for cell isolation/activation/expansion covalently bound to the beads?
Yes. The antibodies are covalently bound and should be very stable in your applications.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.