Magnetic nanoparticles are so useful because they can be immobilised and re-suspended easily by moving them in and out of a magnetic field. The simplest way to do this is by using immobilisation racks consisting of magnet arrays, either for a microtube or microplate format.
Despite their simple construction and lack of moving parts, commercially available immobilization racks are surprisingly expensive. However, they can be assembled easily and cheaply in a laboratory setting. The most critical component of the rack are the magnets themselves- in order to achieve rapid separation, it is best to use high-quality neodymium magnets, N42 grade or above.
We have created a number of different racks that are suitable for specific vessel formats using recycled materials or custom fabricated parts (3D printed or laser cut).
You can find the necessary files for the easy construction of these racks below and on our protocol page.