Preparation Of Magnetic Graphene Nanoparticles And Their Application In Determination Of Antibiotics And Herbicides In Environmental Water Bodies

Magnetic solid phase extraction?MSPE?is a new sample pretreatment method developed in twenty-first Century.The magnetic or magnetic modified materials were used as adsorbent on the basis of SPE,which was convenient,fast and environmentally friendly.Magnetic graphene composites,which combine strong adsorption of graphene and magnetic separation of magnetic materials,are promising adsorbent materials.They have been widely used in food detection,environmental analysis and other fields.The studies of this paper is mainly about:In the first part,the relevant contents of magnetic solid phase extraction were introduced.The magnetic solid phase extraction adsorbent and graphene adsorption material and its application were summarized.In the second part,a magnetic solid phase extraction of graphene oxide-HPLC-MS/MS method has been developed for the determination of eight fluoroquinolone antibiotics in water samples.In order to obtain higher extraction efficiency,the adsorption conditions of magnetic solid phase extraction were optimized.The optimized conditions about this method were:6%ammonia in methanol?v/v?as elution solution,8.0mg GO-Fe₃O₄ as adsorbent,20min adsorption time.Under the conditions,the detection limits of this method were 0.4¹.2 ng/L.This method was utilized to analyze the environmental water samples.The recoveries were ranging from 80.7%to 96.5%and the relative standard deviations?RSDs?were3.4⁸.9%.In the third part,a magnetic solid phase extraction of graphene oxide-HPLC-MS/MS method has been developed for the determination of two microcystins in water samples.The adsorption conditions of magnetic solid phase extraction were optimized,and the optimized conditions about this method were:1‰formic acid in methanol?v/v?as elution solution,10.0mg GO-Fe₃O₄ as adsorbent,15min adsorption time.Under the conditions,the detection limits of the method were0.05¹.0?g/L.This method was utilized to analyze the environmental water samples.The recoveries were ranging from 86.3%to 99.3%and the RSDs were under 8.9%.In the forth part,a magnetic solid phase extraction of aminoated graphene oxide-HPLC-MS/MS method has been developed for the determination of four phenylurea herbicides in water samples.The adsorption conditions of magnetic solid phase extraction were optimized,and the optimized conditions about this method were:methanol as elution solution,15.0mg GO-Fe₃O₄ as adsorbent,15min adsorption time.Under the conditions,the detection limits of the method were 0.03⁰.05?g/L.This method was utilized to analyze the environmental water samples.The recoveries were ranging from 84.3%to 96.4%and the RSDs were 3.9⁸.6%.