Research On Detection Of Dibutyl Phthalate Based On Surface Molecular Imprinting Technology

Dibutyl phthalate（DBP）is a plasticizer that improves the flexibility and plasticity of plastics,and is commonly found in plastic products,as well as in children’s toys,cosmetics,pharmaceuticals and plastic food packaging.DBP is not chemically bonded to plastic molecules,but only through hydrogen bonds or van der Waals forces,and is susceptible to penetration into the environment by external environmental influences,contaminating water and food and causing serious environmental pollution and food safety problems.DBP is chronically and acutely toxic,and when migrating and accumulating in food and the human body,it can adversely affect the reproductive and endocrine systems of living organisms and cause malformations,cancers and genetic mutations in organisms.Phthalates are considered to be one of the hazardous environmental estrogens produced by humans and are classified as a priority contaminant for control by various countries.In view of this,this study developed a Si O₂@MIP electrochemical sensor based on multiwalled carbon nanotubes（MWCNTs）and gold nanoparticles（Au NPs）and a magnetic surface molecularly imprinted polymers（MSMIPs）coupled with a gas chromatography-mass spectrometry（GC-MS）method for the highly sensitive and selective detection of DBP contaminants.In this study,MWCNTs and Au NPs were combined with surface molecularly imprinted polymers（SMIPs）to construct a molecularly imprinted sensor for the highly sensitive detection of DBP.Under the optimal experimental conditions,the response of the Si O₂-COOH@MIP/Au NPs/MWCNTs/GCE to DBP contaminants was in the range of 10^-7-10^-2g L^-1.The results indicate that the designed MIP electrochemical sensor is a promising electrochemical method for the detection of DBP in complex samples.And in this study,the MSMIPs combined with GC-MS were used to develop a rapid and selective detection method for the enrichment of DBP in complex samples.Magnetic nanomaterials encapsulated with Si O₂layers were used as carriers for the synthesis of MSMIPs,increasing the surface area of the polymer.The polymer was characterized and the adsorption performance was studied using isothermal,kinetic and selective adsorption methods.According to the Freundlich isotherm model,the MSMIPs adsorbed as multilayer adsorption on a non-uniform surface;the adsorption was in accordance with the quasi-quadratic model and the adsorption equilibrium was reached around 60 min.The results showed that the addition of magnetic microspheres simplified the pre-treatment process and significantly reduced the pre-concentration time.The feasibility of both methods for the adsorption of DBP on complex samples was verified by establishing the GC-MS method.