▎ 摘　　要

NOVELTY - Biosensor comprises aptamer probe, hairpin probe H1, hairpin probe H2, Klenow Fragment polymerase, Nt.BbvCI endonuclease, buffer liquid and graphene oxide. The nucleotide sequence of the aptamer probe comprises 50 base pair sequence (SEQ ID NO: 1) fully defined in the specification. The aptamer probe is hybridization of aptamer and an amplification template T. The nucleotide sequence of the aptamer comprises a base pair sequence of: (SEQ ID NO: 2). The nucleotide sequence of the amplification template T comprises a base pair sequence of: (SEQ ID NO: 3). The nucleotide sequence of the hairpin probe H1 comprises 46 base pair sequence (SEQ ID NO: 4) fully defined in the specification. The nucleotide sequence of the hairpin probe H2 comprises 46 base pair sequence (SEQ ID NO: 5) fully defined in the specification. USE - The biosensor is useful for detecting tobramycin (claimed). ADVANTAGE - The biosensor detects tobramycin simply and stably with detection limit of 0.06 nM, which is less than existing similar sensor. DETAILED DESCRIPTION - Biosensor comprises aptamer probe, hairpin probe H1, hairpin probe H2, Klenow Fragment polymerase, Nt.BbvCI endonuclease, buffer liquid and graphene oxide. The nucleotide sequence of the aptamer probe comprises 50 base pair sequence (SEQ ID NO: 1) fully defined in the specification. The aptamer probe is hybridization of aptamer and an amplification template T. The nucleotide sequence of the aptamer comprises a base pair sequence of: tgactccaggcacttagtca (SEQ ID NO: 2). The nucleotide sequence of the amplification template T comprises a base pair sequence of: gaggaactggagtcacaagctgagga (SEQ ID NO: 3). The nucleotide sequence of the hairpin probe H1 comprises 46 base pair sequence (SEQ ID NO: 4) fully defined in the specification. The nucleotide sequence of the hairpin probe H2 comprises 46 base pair sequence (SEQ ID NO: 5) fully defined in the specification. An INDEPENDENT CLAIM is included for method for detecting tobramycin by a biosensor, which involves hybridizing the aptamer and the amplification template T into an aptamer probe, adding water and buffer, incubating in a metal bath at 95 degrees C for 3-5 minutes, cooling to obtain the aptamer hairpin structure product, mixing the hairpin probe H1, the hairpin probe H2, water and the buffer solution, incubating in a metal bath at 95 degrees C for 3-5 minutes, obtainng the hairpin structure product after cooling, mixing aptamer hairpin structure product, tobramycin detection substance, 10X smart cut buffer, deoxyribonucleotide triphosphate (dNTP), Nt.BbvCI endonuclease and Klenow fragment polymerase, incubating in a metal bath, adding obtained hairpin structure product to obtain a strand displacement reaction solution, adding graphene oxide solution to the strand displacement reaction solution, after incubating in a metal bath, and measuring fluorescence signal using fluorescence spectrophotometer.