Magnetic nanoparticles: an improved method for mitochondrial isolation.

The ultrastructure, function, and physical and chemical properties of mitochondria have become important issues in scientific research. Current mitochondrial isolation methods mainly rely on the physical and chemical properties of mitochondria. Our team presents a fast and reliable new isolation method based on magnetic nanoparticles binding with monoamine oxidase-A (MAO-A) expressed in the mitochondria. MAO-A is expressed in the outer membrane of human mitochondria and is localized on the cytoplasmic side of the membrane, which makes it possible to isolate the mitochondria effectively, using a magnetic field. As shown in the present study, in comparison with differential centrifugation and density gradient centrifugation, the yield of mitochondria isolated by magnetic nanoparticle binding is higher, with greater mitochondrial purity and activity. The entire process, from cell harvesting to final isolation of the mitochondria, takes approximately 1 h. Magnetic nanoparticles provide a simple, practical approach for mitochondrial isolation.