Method of early diagnosis for alzheimer's disease using phototransistor

PURPOSE: A method for early diagnosing Alzheimer's disease using a phototransistor is provided to enable early diagnosis of the disease and to quantitate cells or beta-amyloid proteins. CONSTITUTION: A method for early diagnosing Alzheimer's disease using a phototransistor comprises: a step of placing the phototransistor for sensing photocurrent difference according to the amount of incident light and a step of sensing photocurrent different according to cells fixed on the surface of a channel layer. The phototransistor comprises the channel layer. The cells have a protein biomarker causing Alzheimer's disease. The protein biomarker is labeled with magnetic particles(200) which are conjugated with multi-proteins. The protein biomarker is beta-amyloid protein(240).