Figure 6.

Magnetic beads can be magnetically manipulated because of their iron core and—with their activated coatings, such as functional groups or specific antibodies—can interact and selectively bind a desired ligand. The most recurrent functionalization for NA extraction is the silica-coating. If the target is human mRNA, the easiest choice is magnetic beads coated with oligo-dT probes [48]. When aiming only at a pathogen detection, functionalization with target specific antibodies is used [41], although this falls outside the aims of the review, devoted to total NA purification.