Contact Person: Ingke-Christine Masthoff
At the TU Braunschweig, the DFG-funded Collaborative Research Center SFB 578 “From gene to product” investigates the biotechnological preparation of recombinant proteins, e.g. antibodies for therapeutic applications. One of the biggest challenges is the selective purification and isolation of the proteins from the culture medium in which they are produced. A promising technology as an alternative to a chromatographic separation is the magnetic separation, segregating the product directly from the culture medium with the help of functionalized magnetic nanoparticles.
At the Institute of Particle Technology being in charge of the subproject C7 of the SFB, an effective, selective and due to optimum regenerability cost-efficient magnetic separation system for the desired protein is developed.
For this purpose first of all very small magnetic nanoparticles (10-20nm) are synthesized via the nonaqueous synthesis. This route permits the precise tuning of the particle size and the crystallinity.
In a second step the particles are functionalized, which means coating the surface with specially designed chemical groups to make a specific binding between desired protein and particle possible, as well as stabilizing them in water.
The used ultra-small nanoparticles possess the advantage of a high specific surface area for interaction with the protein. If an external magnetic field is applied, the particles with the attached proteins are fixed, making a separation of the product and removal of impurities possible. After turning off the magnetic field and successfully separating protein and particle, the nanoparticles can be used for another separation cycle.