▎ 摘　　要

NOVELTY - A capacitance sensor comprises an electrode, a reduced graphene oxide layer formed on the electrode, a cyclodextrin layer sequentially formed on the reduced graphene oxide layer, and an anti-amyloid (β )1-40 antibody that is immobilized on the cyclodextrin layer through host-guest interaction and specifically binds to the amyloid (β )1-40 protein contained in the liquid sample upon contact with the liquid sample and forms a supermolecular inclusion complex between the cyclodextrin and the anti-amyloid (β )1-40 antibody by the host-guest interaction. When the amyloid (β ) 1-40 protein is contained in the liquid sample, the sensor is configured to detect a capacitance change due to binding with an anti-amyloid (β ) 1-40 antibody. Based on the weight of the reduced graphene oxide layer, the content of the cyclodextrin layer is determined 3-12 wt.%. USE - Capacitance sensor used for detecting amyloid (β )1-40 protein in sample e.g. serum (claimed). ADVANTAGE - The sensor is simple and more economical, detects amyloid (β )1-40 protein with high sensitivity, since amyloid (β )1-40 protein contained in a very small amount in the detection sample, and achieves improved detection limit and sensitivity. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: manufacture of capacitance sensor; and method for detecting amyloid (β )1-40 protein in a sample using the capacitance sensor.