Rapid Quantification of Prion Proteins

Prion diseases are a group of fatal transmissible neurological conditions caused by the change in conformation of the normal intrinsic cellular prion protein (PrP^C) in to the highly ordered insoluble amyloid state conformer (PrP^SC). We present a rapid assay using Aptamers and Resistive Pulse Sensing, RPS, to extract and quantify proteins from complex sample matrices, demonstrate with the quantification of PrP^c. We functionalise the surface of superparamagnetic beads, SPBs, with a DNA aptamer. First SPB’s termed P-Beads, are used to pre-concentrate the analyte from a large sample volume. The PrP^c protein is then eluted from the P-Beads before aptamer modified sensing beads, S-Beads, are added. The velocity of the S-Beads through the nanopore reveals the concentration of the PrP^c protein. The process is done in under an hour and allows the detection of picomol’s of protein. The technique could be easily adopted to the mutated version of the protein and integrated into clinical workflows for the screening of blood donations and transfusions.