▎ 摘　　要

NOVELTY - Determination of benalaxyl residual content in tobacco involves adding to-be-tested tobacco sample to polyethylene centrifuge tube, adding acetonitrile, ultrasonically processing, adding sodium chloride, layering, purifying with a reagent package comprising anhydrous magnesium sulfate and N-propylethylenediamine adsorbent, filtering, obtaining a to-be-tested sample, mixing potassium ferricyanide and potassium chloride with water, obtaining potassium ferricyanide buffer, mixing with acetonitrile and benalaxyl stock solution, detecting, drawing standard curve, assembling electrochemical workstation by placing graphene-modified benalaxyl-imprinted electrochemical sensor, a platinum electrode and a saturated calomel electrode in potassium ferricyanide buffer, measuring the to-be-tested sample with the electrochemical workstation, and calculating benalaxyl residual content in the sample using observed values and standard curve. USE - Determination of benalaxyl residual content in tobacco. ADVANTAGE - The method enables simple, economical and rapid determination of benalaxyl residual content in tobacco with high accuracy, sensitivity and selectivity. DETAILED DESCRIPTION - Determination of benalaxyl residual content in tobacco involves dispersing 2 mg graphene in 2 ml ultrapure water, ultrasonically processing for 1 hour, obtaining a suspension (s1), placing the screen printed electrode in ultrapure water, ultrasonically cleaning for 1 hour, drying, washing with sulfuric acid, drying, dripping 5 mu L suspension (s1), irradiating with infrared light for 15 minutes, obtaining a graphene-modified electrode, dissolving 0.0125 mmol benalaxyl, 0.05 mmol acrylamide and 0.75 mmol ethylene glycol dimethacrylate in 0.5 ml acetonitrile, ultrasonically processing for 5 minutes, adding 0.24 mmol azobisisobutyronitrile, ultrasonically dispersing, purging nitrogen gas for 10 minutes, obtaining a prepolymerized liquid, coating resultant on the graphene-modified electrode, irradiating with UV at 365 nm for 3 hours, cooling to room temperature, obtaining graphene-modified benalaxyl-imprinted electrochemical sensor, eluting with mixture comprising methanol and acetic acid in volume ratio of 1:1, removing benalaxyl molecules, obtaining an electrochemical sensor, adding 1 g to-be-tested tobacco sample to 25 ml polyethylene centrifuge tube, adding 10 ml acetonitrile, ultrasonically processing for 10 minutes, adding 2 g sodium chloride, layering, purifying with a reagent package comprising 150 mg anhydrous magnesium sulfate and 25 mg N-propylethylenediamine adsorbent, filtering, obtaining a to-be-tested sample, mixing 0.1646 g potassium ferricyanide and 0.7455 g potassium chloride with 100 ml water, obtaining potassium ferricyanide buffer, mixing resultant with acetonitrile and benalaxyl stock solution, detecting, drawing standard curve, assembling electrochemical workstation by placing the electrochemical sensor as a working electrode, a platinum electrode as an auxiliary electrode and a saturated calomel electrode as a reference electrode in 10 ml potassium ferricyanide buffer, measuring the to-be-tested sample with the electrochemical workstation at scanning rate of 100 mV/second, potential increase of 0.004 V, amplitude of 0.05 V and pulse width of 0.05 second, and calculating benalaxyl residual content in the sample using observed values and standard curve.