Patent ID: 9023607
Filing Date: 2015-05-05
Classification: B82Y,G01N

Abstract:
1. A method for diagnosing Alzheimer's disease by detecting the presence of beta-amyloid in cells using a phototransistor device, comprising: providing cells that potentially contain beta-amyloid; labeling the cells with a multi-protein that selectively binds to beta-amyloid if present and that includes streptavidin, biotin and polyethylene glycol connected in sequence with the streptavidin being bound to a magnetic bead and the polyethylene glycol being directly bound to the beta-amyloid if present, to provide labeled cells; providing a phototransistor device for sensing a photocurrent level according to intensity of incident light, said phototransistor device including a channel layer; illuminating the phototransistor and sensing a first photocurrent corresponding to the incident light; selectively fixing said labeled cells on a surface of the channel layer by applying an external magnetic field effective to attract the magnetic bead to the phototransistor device through a permanent magnet positioned below the channel layer; illuminating the phototransistor and sensing a second photocurrent corresponding to said incident light after the labeled cells, if any, are fixed on the surface of the channel layer; and detecting any difference between the first and second photocurrents so that the presence of, and optionally amount of, labeled beta-amyloid in said cells is indicated and Alzheimer's disease may be diagnosed.