▎ 摘　　要

NOVELTY - Fluorescent probe comprises riboflavin and graphene oxide, where the riboflavin is combined with graphene oxide through π-π conjugation and hydrogen bonding, and is adsorbed on the surface of graphene oxide. USE - The probe is useful in detecting norfloxacin content in veterinary medicine (all claimed). ADVANTAGE - The probe: competitively adsorbs riboflavin RF and norfloxacin NOX on the surface of graphene oxide (GO); realizes the determination of norfloxacin NOX concentration through the change of fluorescence intensity; detects norfloxacin at a lower concentration; has excellent anti-interference ability and excellent ood selectivity for different anions, so that the detection of norfloxacin does not require complicated pretreatment; reduces the detection difficulty; is different from the shortcomings of traditional methods e.g. complicated pretreatment, expensive device and a large amount of reagents; and has simple operation, high speed, high efficiency, high sensitivity, and excellent application prospect. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for: preparing the fluorescent probe, comprising oscillating riboflavin diluent and graphene oxide dispersion liquid, uniformly mixing, allowing to stand at room temperature, fully adsorbing riboflavin on the surface of graphene oxide to obtain the finished product; and use method of the fluorescent probe in detecting norfloxacin content, comprising adding fluorescent probe to the sample to be tested containing norfloxacin, replacing the norfloxacin in the sample to be tested by the riboflavin on the surface of the graphene oxide, desorbing the riboflavin from the graphene oxide surface, recycling fluorescence of riboflavin, and determining the content of norfloxacin in the sample to be tested by the change amount of the fluorescence intensity.