▎ 摘　　要

NOVELTY - A FAM(RTM: 5-Carboxyfluorescein) fluorescently labeled nucleotide aptamer capable of detecting nitrofurazone (NFZ), is new, where the aptamer comprises NFZ8 aptamer having a 90 base pair sequence (SEQ ID NO: 1) fully defined in the specification, NFZ24 aptamer having a 90 base pair sequence (SEQ ID NO: 2) fully defined in the specification, NFZ28 aptamer having a 90 base pair sequence (SEQ ID NO: 3) fully defined in the specification, NFZ34 aptamer having a 90 base pair sequence (SEQ ID NO: 4) fully defined in the specification or NFZ70 aptamer having a 90 base pair sequence (SEQ ID NO: 5) fully defined in the specification and the aptamer derivative obtained by modifying or transforming the aptamer, is new. USE - The FAM (RTM: 5-Carboxyfluorescein) fluorescently labeled nucleotide aptamer, GO based fluorescent aptasensor or kit is useful for quantitative detection of NFZ in aquatic product culture water test sample (claimed). ADVANTAGE - The aptamer has improved affinity, which is 2.5 times higher compared to original aptamer. The kit has high sensitivity, strong specificity and rapid action and is simple to use and cost-effective. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: method (M1) for preparing the FAM (RTM: 5-Carboxyfluorescein) fluorescently labeled aptamer; graphene oxide (GO) based fluorescent aptasensor comprising (a) FAM (RTM: 5-Carboxyfluorescein)-NFZ8-1, where the NFZ8-1 aptamer has base pair sequence of SEQ ID NO: 6, (b) GO and (c) binding buffer solution; kit comprising the GO based fluorescent aptasensor; and method (M2) for using the kit involves (a) processing each actual sample in accordance with the requirements, (b) mixing and shaking the treated sample with FAM (RTM: 5-Carboxyfluorescein)-NFZ8-1 for 30 minutes, (c) adding GO and continuing shaking for 10 minutes and (d) centrifuging, absorbing the supernatant and measuring the fluorescence value. gttctattgaaaaaac(SEQ ID NO: 6).