▎ 摘　　要

NOVELTY - A graphene oxide optical biological sensor preparing method involves dispersing nanographene oxide in deionized water to obtain 1 mg/ml graphene oxide dispersion liquid, processing the graphene oxide dispersion liquid in ultrasonic ice water bath at 3000 revolutions/minute for 30 minutes, and obtaining supernatant, where the supernatant is good graphene oxide dispersion. Cross-linking polypeptide is added to the graphene oxide dispersion to obtain the product. USE - Method for preparing graphene oxide optical biological sensor that is utilized in detecting TNT target molecules. ADVANTAGE - The method enables preparing graphene oxide optical biological sensor in a simple manner, with TNT specific sensibility, high sensitivity, low detection limits, strong and better stability and unique optical properties. DETAILED DESCRIPTION - A graphene oxide optical biological sensor preparing method involves dispersing nanographene oxide in deionized water to obtain 1 mg/ml graphene oxide dispersion liquid, processing the graphene oxide dispersion liquid in ultrasonic ice water bath at 3000 revolutions/minute for 30 minutes, and obtaining supernatant, where the supernatant is good graphene oxide dispersion. Cross-linking polypeptide is added to the graphene oxide dispersion by adding 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) powder to the graphene oxide dispersion, where the mass ratio of EDC, NHS and graphene oxide dispersion is 1:1:1, processing the graphene oxide dispersion liquid in ultrasonic ice water bath for 1 hour to obtain suspension, adding sodium hydroxide solution to the suspension to regulate pH at 8, dispersing synthetic 2,4,6-trinitrotoluene (TNT) polypeptide in 0.1 M phosphate buffered saline (PBS) to obtain 250 mg/ml TNT polypeptide solution, adding the polypeptide solution to the suspension, where volume ratio of the suspension and polypeptide solution is 10:1, regulating pH of the mixture at 8, maintaining the mixture overnight under dark conditions, centrifuging the mixture at 13000 revolutions/minute for 30 minutes, obtaining precipitate, washing the precipitate with deionized water repeatedly for 3 times, re-dispersing the precipitate in water, adding the graphene oxide dispersion liquid to the mixture and storing the product at 4 degrees C.