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Find out which magnetic bead chemistry meets your application requirements in Magbeads 101: A guide to choosing and using magnetic beads and explore ways to optimize your magnetic bead workflow in Scientists guide to magnetic beads

How to covalently couple proteins to carboxylate-modified magnetic beads

The convenient “one-step” protocol for covalent coupling of proteins to Sera-Mag™ carboxylate-modified particles or Sera-Mag™ SpeedBeads carboxylate-modified particles involves the following steps

1. Prepare a reagent mixture containing MES buffer, protein solution, and magnetic particles, and mix for 15 minutes at room temperature on a mixing wheel or other device.
2. Add freshly prepared EDAC solution at the pre-determined optimal concentration, and mix for one hour at room temperature on a mixing wheel or other device.
3. Pellet particles by centrifugation (10 to 30 minutes in a standard microcentrifuge) and decant the supernatant.
4. Perform two washes with MES buffer or a high pH buffer of your choice, pelleting particles by centrifugation and using ultrasonication to resuspend pellets between washes.
5. Resuspend final pellet to desired % solids with a buffer such as MES that does not contain blocking proteins.
6. Perform a BCA protein assay to determine the amount of protein bound on the particles.

Have you considered your magnetic separation rack?

Cytiva’s Magnetic Separation Rack 15 mL is a 3D printed, magnetized tube rack with a strong, removable magnetic force and easy pipette access. It facilitates high capture, retention, and release of magnetic beads from various liquid sample media, allowing high-throughput, parallel processing of up to six 15 mL samples.

Find out more about magnetic separation racks