▎ 摘　　要

NOVELTY - Biosensor comprises a reaction unit in which a physical or chemical interaction occurs with a target material in a sample, where the reaction unit comprises reduced graphene oxide (rGO). USE - The biosensor is useful for detecting a target material in a urine sample. The target material is chosen from an antigen, a hapten, a carbohydrate, a protein, a drug, a microorganism, an antibody and a nucleic acid capable of participating in a sequence-specific hybridization reaction with a complementary sequence. The target material is a prostate cancer marker (all claimed). ADVANTAGE - The biosensor non-invasively, rapidly and accurately diagnoses prostate cancer, detects target material with high sensitivity and specificity, exhibits excellent durability, stability, linearity and low limit of detection (LOD) of 10 fM and performs quantitative analysis of a wide range of biomarker concentrations. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for detecting a target material, which involves contacting the sample to the biosensor and observing a change in electrical conductivity of the biosensor.