Superparamagnetic Nanoparticle Capture of Prions for Amplification

Prion diseases are associated with the presence of PrPSc, a disease-associated misfolded conformer of the prion protein. We report that superparamagnetic nanoparticles bind PrPSc molecules efficiently and specifically, permitting magnetic separation of prions from a sample mixture. Captured PrPSc molecules retain the activity to seed protein misfolding cyclic amplification (PMCA) reactions, enabling the rapid concentration of dilute prions to improve detection. Furthermore, superparamagnetic nanoparticles clear contaminated solutions of PrPSc. Our findings suggest that coupling magnetic nanoparticle capture with PMCA could accelerate and improve prion detection. Magnetic nanoparticles may also be useful for developing a nontoxic prion decontamination method for biologically derived products.