surface modify of Iron oxide nanoparticle and stabilized by polymer then might be pre-concentrate to Fungi. Alike, bacteria has overall negative surface charge, in case of Fungi need to know before proceeding for experiment. In that case it could be pre-concentrate and even detect.
Sorry , i don't find the paper. MNPs are now widely used for sample preparation in the detection of microorganisms. Here is a book chapter for your reference.
Luo, Pengju G.; Stutzenberger, Fred J. Nanotechnology in the detection and control of microorganisms. ADVANCES IN APPLIED MICROBIOLOGY, VOL 63 : Advances in Applied Microbiology 63: 145-+ 2008
Fungi must be chemically bonded to magnetite nanoparticles so that it can be isolated from a mixture with proteins, sugars, bacteria.If you mix mycelium of mushrooms with magnetite nanopowder, then this mixture can be transferred using a magnet to another place.