Research On Analysis And Detection Of Trace Organic Pollutants With Novel Magnetic Enrichment Materials

Persistent organic pollutants are widely present in the environment and easily invade human and animal,which have unpredictable potential harm.Therefore,it is vital that the analysis and detection of trace organic pollutants residues in environmental water samples,food samples and biological samples.The three-dimensional flower-like magnetic carbon material and magnetic ionic liquids have simple and rapid separation by an external magnetic field,which is beneficial to save the time for sample pretreatment.Therefore,three-dimensional flower-like Fe₃O₄@C and four magnetic ionic liquids containing different anions(MILs,[P⁺_6,6,6,14][FeCl₄^-],[P⁺_6,6,6,14]₂[MnCl₄^2-],[P⁺_6,6,6,14]₂[CoCl₄^2-]and[P⁺_6,6,6,14]₂[NiCl₄^2-])as extractants of magnetic solid phase extraction?MSPE?and dispersive liquid liquid microextraction?DLLME?respectively combined with high performance liquid chromatography?HPLC?analysis and detection of four non-steroidal anti-inflammatory drugs and six estrogens.The basic research content of this article is as follows:1.A lower cost-effective and simpler synthesis method was applied to acquire three-dimensional flower-like structure Fe₃O₄/C for extraction non-steroidal anti-inflammatory drugs?NSAIDs?from complex environmental and biological samples coupled with HPLC-UV determination.The parameters of magnetic solid-phase extraction?MSPE?were optimized by univariate and multivariate methods?Box-Behnken design?,including mass of adsorbents,extraction time,pH,ionic strength,ect.Under optimized conditions,this method yielded good recoveries?89.6-107.0%?,wide linear range(2.5-1000 ng mL^-1)and lower limits of detection(0.25-0.5 ng m L^-1).In addition,the adsorption of NSAIDs on Fe₃O₄/C sorbent was studied by applying adsorption isotherms and kinetic studies.Moreover,adsorption mechanism for NSAIDsby Fe₃O₄/C was proposed,which was hydrogen bonding and?-?interaction betweenNSAIDs and Fe₃O₄/C.2.Several magnetic ionic liquids?MILs?,[P⁺_6,6,6,14][FeCl₄^-],[P⁺_6,6,6,14]₂[MnCl₄^2-],[P⁺_6,6,6,14]₂[CoCl₄^2-]and[P⁺_6,6,6,14]₂[NiCl₄^2-]were synthesized and applied for the extraction of six estrogens?estrone,estradiol,17-?-hydroxyprogesterone,chloromadinone 17-acetate,megestrol 17-acetate and medroxyprogesterone 17-acetate?in dispersive liquid-liquid microextraction?DLLME?.The[CoCl₄^2-]-based MIL was selected as extraction solvent for the separation and concentration of estrogens from milk and cosmetics due to its visual recognition,no sign of hydrolysis,solution acquisition easier and highest extraction capacity.In addition,the[CoCl₄^2-]-based MIL with low UV absorbance allows direct analysis of the extraction solvent by HPLC-UV.The influence of the mass of MIL,extraction time,salt concentration,and the pH of the sample solution were investigated to obtain optimized extraction efficiency.Besides,extraction conditions including salt concentration,mass of MIL and extraction time were further optimized by the Box-Behnken design through the response surface method.Under optimized conditions,the limits of detection?LODs?of all estrogens were ranged from 5 ng mL^-1 to 15 ng m L^-1.The recoveries ranging from 98.5%to 109.3%in milk and from 96.3%to 111.4%in cosmetics were also studied,respectively.In addition,the proposed method was statistically compared with the reported conventional ILs-DLLME method and the National standard methods of food safety and cosmetics.The experimental results showed that the functionalized MIL could successfully applied for extraction,separation and pretreatment of estrogens in milk and cosmetics.