Preparation And Application Of A Novel Fluorescence Molecular Imprinted Sensor Based On Dioctyl Phthalate

Dibutyl phthalate?DEHP?is a commonly used plasticizer,which is widely used in the plastic of daily life.The large amount of plastic is used to increase its polluted in the environment.Its harmfulness attracts to the attention of researcher,and mainly interferes with the biological endocrine system.A simple and quick way to detection the content in the environment is needed,and the fluorescent molecularly imprinted sensor has this feature.Preparation of molecularly imprinted polymer by surface molecular imprinting technology have been high selectivity to analytes,and fluorescent sensors have been with high sensitivity to analytes.The combination can quickly recognition specific analysis.In this paper,through the optical properties of ZnO quantum dot,fluorescein isothiocyanate)and different fluorescence color of CdTe quantum dots combined with molecular imprinting polymer specificity recognition,were prepared the three different kinds of fluorescence molecularly imprinted sensor to sensitivity recognition DEHP,respectively.Top water,Yudai river and mineral water are used as actual samples to verify the applicability of fluorescent molecular imprinting sensors.The experiment is divided into three parts,which are as follows:?1?Preparation and properties of single launch fluorescent sensors on the surface of the ZnO research:first,using simple solvothermal method to get rods of ZnO quantum dots,and then in the surface modification of carbon carbon double bond.By precipitation polymerization method,fluorescence molecularly imprinted polymer was preparation.The polymers were used as the identification element of the fluorescent sensor and applied to the detection of DEHP.Fluorescence molecularly imprinted polymers were detected by transmission electron microscopy,X-ray diffraction,scanning electron microscopy and infrared spectroscopy.In this sensor,ZnO quantum dots can produce obvious fluorescence quenching and realize rapid and specific recognition of DEHP.By optimizing the experimental analysis conditions,the linear correlation coefficient was 0.9923,and the minimum detection limit was 1.3nmol L^-1.The analogue structure of DEHP is used as a reference experiment to verify the selectivity of fluorescent imprinted polymers.It was successfully applied to the detection of DEHP in the actual sample,and the recovery rate was greater than97.50%,and the relative standard deviation was lower than 3.18%.?2?Preparation and performance of single emission isothiocyanic acid fluorescence molecularly imprinted sensor:amino modified silicon dioxide nanoparticles were preparation,and then their surface grafting fluorescein?isothiocyanic acid?through the reaction of amino.3-aminopropyl triethoxysilane as functional monomer synthesis molecularly imprinted polymer layer on silicon dioxide surface,and successfully preparation fluorescent molecularly imprinted sensor.The morphology and structure of fluorescent molecularly imprinted polymers were measured by TEM,XRD,SEM and FTIR.Fluorescence intensity,concentration,adsorption equilibrium time and stability are Optimized,and the 6 of pH value shows the best fluorescence intensity and adsorption capacity.According to the Stern-Volmer equation,the linear relationship between DEHP concentration and the fluorescence intensity of the sensor was calculated,and the linear range was 0.2².4?mol L^-1,and the linear correlation coefficient was 0.995.The selective experiment was conducted by using the structure analogue of DEHP as interferent.The recovery rate was greater than 98.33%and the relative standard deviation was 4.03%⁴.56%,using the Yudai river water as the actual sample.?3?Preparation and performance of ratio fluorescence molecularly imprinted sensor on the surface CdTe quantum dots:The heating refluxing method were synthesis the different sizes and luminescence colors CdTe quantum dots with the sulfhydryl modification.The surface of red light quantum dots coated by silicon dioxide layer,and then modified the amino group.The green fluorescence of CdTe after the carboxylation reaction of sulfhydryl group was grafted onto the particles surface by the reaction with the amino reaction.Finally,the surface molecularly imprinted polymer was prepared by polymerization,and realized selectively recognition DEHP with visual detection.The morphology and structure of fluorescence molecularly imprinted polymers were obtained by TEM,fluorescence spectrophotometer,XRD,SEM and FTIR.The fluorescence color can be seen by UV light.The linear correlation coefficient is 0.99018,and the minimum detection limit is1.62 nmol L^-1.The local purchased mineral water was used as the actual sample,and the recovery rate was greater than 98.00%and the relative standard deviation was less than 3.18%.