▎ 摘　　要

NOVELTY - Biosensor comprises surface-modified electrodes with graphene oxide (RGO), target material-specific aptamer fixed to the electrode, and unit for measuring oxide-reduction potential of the electrode, where the target material is bonded to the aptamer. USE - The biosensor is useful for detecting target material chosen from metal ion, DNA, RNA, ATP and protein chosen from thrombin, fibrinogen, immunoglobulin G (IgG), IgM, IgA, IgD, hemoglobin, myoglobin, albumin, casein, prolamine, actin, myosin, collagen and keratin (all claimed). ADVANTAGE - The biosensor simply and cost-effectively detects target material, and has excellent sensitivity. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for detecting target material, which involves immersing electrode in graphene oxide solution to obtain surface-modified electrode, immobilizing specific aptamer on the surface-modified electrode, bonding the target material to the aptamer on the surface-modified electrode, and measuring electrochemically reduced-reduction potential.