▎ 摘　　要

NOVELTY - A graphitic carbon nitride (g-C3N4) nanosheet/graphene oxide composite material (CNNS/GO) is prepared by taking melamine in crucible, heating in muffle furnace under atmospheric environment at 550 degrees C for 2-4 hours at rate of 2-5 degrees C/minute, preferably 2 degrees C/minute, grinding into powder, heating to 540 degrees C for 3-4 hours to obtain Bulk-g-C3N4, dispersing in distilled water, continuously ultrasonically processing for greater than or equal to 10 hours, centrifuging to form white suspension at speed of 4500 revolutions/minute (rpm), separating to obtain CNNS suspension, preparing graphene oxide using Hummers method, ultrasonically processing graphene oxide powder in in deionized water for 1-3 hours to prepare graphene oxide dispersion, and ultrasonically treating CNNS suspension and graphene oxide dispersion at mass ratio of 1-7:1 for 3-5 hours. USE - The method is used for preparing graphitic carbon nitride nanosheet/graphene oxide composite material. ADVANTAGE - The method is fast, simple and convenient, has simple apparatus, low analysis cost, obtains high selectivity in complex environmental medium, and realizes highly sensitive detection and analysis of acetaminophen and levofloxacin. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for: (1) preparation of the CNNS/GO modified electrode comprising polishing of bare glassy carbon electrode (GCE) with 0.05 mu m alumina particle, carefully washing with ultra-pure water and ethanol to obtain mirror surface, drying, removing 6-8 mu L CNNS/GO on GCE surface, and drying under infrared lamp; and (2) detecting acetaminophen (AC) and levofloxacin (LEV) with CNNS/GO modified electrode comprising preparing a series of AC and LEV standard solutions of different concentrations, using CNNS/GO modified electrode as working electrode, platinum wire electrode as counter electrode and silver-silver chloride electrode as reference electrode, putting three electrodes in solution with 0.1 M phosphate buffer (pH = 5) as electrolyte, detecting different concentrations of AC in the presence of 5 mu M LEV or different concentrations of LEV in the presence of 10 mu M AC, checking AC and LEV, using differential pulse voltammetry (DPV) method to record peak currents corresponding to different concentrations of AC and LEV, and drawing standard curves for AC and LEV analysis according to peak current value and corresponding AC and LEV concentrations in standard solution.