▎ 摘　　要

NOVELTY - Preparing ferromanganese magnetic graphene oxide lead ion imprinting material comprises (i) preparing manganese ferrite nanoparticles; (ii) dispersing manganese ferrite nanoparticles ultrasonically in a mixed solution of 50-300 ml ethanol and water with a volume ratio of 4:1, adding aqueous ammonia solution, and stirring; (iii) ultrasonically dispersing graphene oxide in dimethylformamide, dimethyl sulfoxide or acetone, adding 0.1-0.3 g carboxy activating reagent, adding manganese ferrite-silicon dioxide-amino nanoparticles, stirring, ultrasonically washing and drying; (iv) taking manganese ferrite-silicon dioxide-amino-functionalized graphene oxide nanoparticles and dispersing; (v) obtaining crude manganese ferromagnetic graphene oxide lead ion imprinting material; and (vi) eluting crude ferromanganese magnetic graphene oxide lead ion imprinting material, grinding and soaking in hydrochloric acid, washing the product with water until it is neutral, vacuum drying the product at 50 degrees C. USE - The material is useful to remove lead in aqueous samples, preferably tobacco, soil and vegetable (all claimed). ADVANTAGE - The material has high selectivity and adsorption performance, good recycling performance, and wide range of applications, and wide range of application prospects in the rapid magnetic separation, enrichment and analysis of biological samples, environmental samples, and food. DETAILED DESCRIPTION - Preparing ferromanganese magnetic graphene oxide lead ion imprinting material comprises (i) preparing manganese ferrite nanoparticles; (ii) dispersing 0.5-2 g manganese ferrite nanoparticles ultrasonically in a mixed solution of 50-300 ml ethanol and water with a volume ratio of 4:1, adding 2.5 ml aqueous ammonia solution, and stirring for 30 minutes at 30 degrees C; (iii) ultrasonically dispersing graphene oxide in dimethylformamide, dimethyl sulfoxide or acetone, adding 0.1-0.3 g carboxy activating reagent, adjusting the pH of the solution to 4-6, stirring at 30 degrees C for 2 hours, adding manganese ferrite-silicon dioxide-amino nanoparticles, stirring for 12 hours, ultrasonically washing the magnetic separation reaction product with water, and drying; (iv) taking 100-500 mg manganese ferrite-silicon dioxide-amino-functionalized graphene oxide nanoparticles and dispersing in 160 ml absolute ethanol for 60 minutes, adding 0.1 mol/l aqueous ammonia solution to adjust the pH to 8, dispersing 5 ml second silicon reagent into 20 ml absolute ethanol, dropping to the above solution, stirring and reacting at 60 degrees C for 24 hours, washing the magnetic separation reaction product for 3 times with absolute ethanol and deionized water respectively, drying in vacuum at 50 degrees C; (v) dispersing 0.1-2 mmol ligand and 0.1-2 mmol functional monomer in 25 ml acetonitrile, adding 0.10-1 mmol lead nitrate, and stirring at room temperature for 5 hours, pouring 20-300 mg manganese ferrite-silicon dioxide-amino-functionalized graphene oxide-vinyltriethoxysilane, 1-10 mmol crosslinking agent and 0.02-0.20 mmol azobisisobutyronitrile, heating to 50-75 degrees C in an inert gas atmosphere C, stirring reaction for 6-24 hours and magnetically separating to obtain crude manganese ferromagnetic graphene oxide lead ion imprinting material; and (vi) eluting the crude ferromanganese magnetic graphene oxide lead ion imprinting material for many times with a mixture of methanol and distilled water in a volume ratio of 1:4 to remove the reaction raw materials, drying, grinding and soaking in 1-4 mol/l hydrochloric acid for 4-24 hours elution until lead-free ions in the filtrate are detected, washing the product with water until it is neutral, vacuum drying the product at 50 degrees C. An INDEPENDENT CLAIM is also included for use method of material to remove lead in aqueous samples, comprising either (ai) activating 5-50 mg lead ion imprinting material with 5 ml anhydrous methanol, magnetically separating and washing twice with 10 ml distilled water, (aii) adding the activated lead ion imprinting material to 20 ml aqueous solution sample containing lead ions, adjusting the pH of the solution to 3-7, oscillating at 25 degrees C, and performing a solid phase extraction experiment with a contact time of 5-90 minutes, and (aiii) magnetically separating the lead ion imprinting material and the aqueous solution sample, rinsing the lead ion imprinting material with 5 ml distilled water, 5 ml eluent and 5 ml eluent, respectively, passing magnetically separated aqueous solution sample through a 0.45 mu m membrane, and detecting the lead ion concentration or (bi) pre-drying biological samples and crushing through a 200-mesh sieve, (bii) taking 0.1-1 g sample into the digestion tube, adding 6 ml concentrated nitric acid and 2 ml hydrogen peroxide in turn, sealing and microwave digesting, dropping to room temperature and take out the digestion tube, heating to 80-120 degrees C to volatilize to remove the acid and concentrate the volume of the mixture to 1 ml, adjusting the pH value with pH of 6.5 buffer solution and transferring to a volumetric flask, rinsing the digestion tube 3-4 times, combining into the volumetric flask and diluting to 50 ml with the buffer solution, shaking well to prepare an activated biological sample solution, (biii) taking 5-50 mg lead ion imprinting material and activating with 5 ml anhydrous methanol and magnetically separating, washing twice with 10 ml distilled water, magnetically separating and preparing the activated lead ion imprinting material, (biv) adding 50 ml activated biological sample solution into the lead ion imprinting material, shaking at 25 degrees C for 30 minutes, magnetically separating, washing with 5 ml distilled water, 5 ml eluent and 5 ml eluent respectively, magnetically separating lead ion imprinting material step by step, collecting the solution, passing through a 0.45 mu m membrane and detecting the lead ion concentration.