▎ 摘　　要

NOVELTY - Biosensor comprises a target material which is labeled with a metal particle and a probe substance which is conjugated to a graphene oxide with fluorescence characteristic. USE - The biosensor and method are useful to optically identify the presence of target (claimed). ADVANTAGE - The biosensor optically identifies the presence of target by inexpensive process, and has reliability, improved reproducibility and profitability. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for biosensing method, which involves contacting the target material with the probe, and measuring graphene oxide fluorescence intensity.