▎ 摘　　要

NOVELTY - Electrochemical sensor for detecting beta -amyloid oligomers is prepared by depositing gold nanoparticles on vertical graphene-carbon cloth electrode followed by immersing clean vertical graphene-grown carbon cloth electrode in chloroauric acid solution for constant potential electrodeposition; immersing gold nanoparticle-modified vertical graphene/carbon cloth electrode in thiolated prion protein solution and incubated at room temperature, providing mercaptohexanol solution which seals surface of electrode to eliminate non-specific binding sites to prepare prion protein modified electrode; incubating prepared prion protein modified electrode with different concentrations of A beta oligomer solution to identify A beta oligomers at room temperature; mixing aptamer-T30 and L-ascorbic acid fully at room temperature, then adding copper sulfate pentahydrated (CuSO4x 5H2O) solution, and stirring at room temperature in dark to obtain aptamer-poly T-copper nanocluster conjugate solution. USE - Electrochemical sensor for detecting beta -amyloid oligomers used for diagnosis and treatment of Alzheimer disease. ADVANTAGE - The electrochemical biosensor has high sensitivity, low detection limit, high specificity and good stability; shows feasibility in detection of human serum sample; and has important meaning for early diagnosis and treatment of Alzheimer disease. DETAILED DESCRIPTION - Electrochemical sensor for detecting beta -amyloid oligomers is prepared by depositing gold nanoparticles on vertical graphene-carbon cloth electrode followed by immersing clean vertical graphene-grown carbon cloth electrode in chloroauric acid solution for constant potential electrodeposition; immersing gold nanoparticle-modified vertical graphene/carbon cloth electrode in thiolated prion protein solution and incubated at room temperature, providing mercaptohexanol solution which seals surface of electrode to eliminate non-specific binding sites to prepare prion protein modified electrode; incubating prepared prion protein modified electrode with different concentrations of A beta oligomer solution to identify A beta oligomers at room temperature; mixing aptamer-T30 and L-ascorbic acid fully at room temperature, then adding copper sulfate pentahydrated (CuSO4x 5H2O) solution, and stirring at room temperature in dark to obtain aptamer-poly T-copper nanocluster conjugate solution, incubating solution with electrode after identifying A beta oligomer to prepare A beta oligomer electrochemical sensor, where amino acid sequence of thiolated prion protein is 16 amino acids (SEQ ID NO: 2), given in the specification, and DNA sequence of nucleic acid aptamer-T30 is 54 nucleotides (SEQ ID NO: 1), given in the specification.