▎ 摘　　要

NOVELTY - A sensor is prepared by binding nucleic acid sequence and graphene oxide. USE - Sensor used for detecting heavy mercuric ion (claimed). ADVANTAGE - The sensor has improved detection sensitivity, and is economical. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for method for preparing the sensor, which involves (a) preparing an aqueous solution of graphene oxide, (b) synthesizing mercuric ion (Hg2+)-nucleic acid sequence of 5'-tttgcttgttgcgcttcttgcttt-3' (SEQ ID NO: Not defined), (c) labeling the obtained nucleic acid sequence by inserting the nucleic acid sequence with SYBR Green I (RTM: N',N'-dimethyl-N-(4-((E)-(3-methyl-1,3-benzothiazol-2-ylidene)methyl)-1-phenylquinolin-1-ium-2-yl)-N-propylpropane-1,3-diamine), and carrying out fluorescence, and (d) performing fluorescence quenching by adding nucleic acid sequence to the aqueous solution of graphene oxide and processing mixture for overnight.