text: SOFIA has been used to rapidly detect the abnormal form of the prion protein (PrP) in samples of bodily fluids, such as blood or urine. PrP is the marker protein used in diagnostics for transmissible spongiform encephalopathies (TSEs), examples of which include bovine spongiform encephalopathy in cattle (i.e. “mad cow” disease), scrapie in sheep, and Creutzfeldt–Jakob disease in humans. Currently, no rapid means exists for the ante mortem detection of PrP in the dilute quantities in which it usually appears in bodily fluids. SOFIA has the advantages of requiring little sample preparation, and allowing for electronic diagnostic equipment to be placed outside the containment area.