Study On Novel Analytical Method For Sensitive Detection Of Phenylethanolamine A Based On Metal Organic Frame Combined With Molecularly Imprinted Polymers

Phenylethanolamine A(PEA)is a kind of β-agonists and its property is similar with the compounds such as clenbuterol,ractopamine,etc.PEA could prompt the increase of animal and improve the ratio of lean meat.However,PEA possesses strong toxicity because its residue is easily found in animal tissue.PEA has been immediately prohibited in China in the form of announcement of the Ministry of Agriculture(No.1619)when it was confirmed in 2011.Tt is necessary,therefore,to develop sensitive and robust analytical method to monitor the illegal application of PEA in animal breeding.In this study,two novel analytical methods were presented to detect PEA in anaimal urine,which innovatively combined metal organic framework materials(MOFs)and molecularly imprinted polymers(MIP)and make full use of MOFs characters such as orderly pore size,large specific surface area and the specificity recognition ability of MIP.The main research is as follows:1.Synthesis of MIP@MOF-5 and its application in determiantion of PEA on UPLC-MS/MSIn this study,MIP was produced on the surface of MOF-5 with PEA as template,methacrylic acid as monomer and EGDMA as linker and MIP@MOF-5 was obtained.X-ray diffraction(XRD)and scanning electron microscope(SEM)were used to characterize the structure and morphology of MIP@MOF-5.The adsorption performance and selectivity of MIP@MOF-5 were examined in detailed.The conditions of adsorption and elution were optimized.The eliminating efficiency of animal urine sample matrix was studied.Furthermore,analytical method for determination of PEA in animal urine was developed based on clean-up and enrichment of MIP@MOF-5 followed UPLC-MS/MS detection.Under optimum conditions,the linear range of the developed method was from 1 to 100 ng/mL with good linearity of 0.996.The limit of detection(LOD)and limit of quantification(LOQ)were 0.1 ng/mL and 0.5ng/mL,respectively.The recoveries of target analytes were from 83.9%to 102.5%with lower RSD of 6.5%under different spiked level in anaimal urine.It has been found that MIP@MOF-5 was suit for enrichment and clean-up of target analytes in complicated sample matrix,because it possessed some advantages including high regularity,large adsorption capacity and excellent selectivity,etc.2.The construction of ultrasensitive electrochemical sensor based on MOFs-MIP and its application in detection of PEAThis study innovatively constructed a kind of MIP composite membrane electrochemical sensors with the recognition of biological type based MOFs concept and an ultrasenitive detection of PEA in animal urine was achieved.The polished gold electrode was modified with PATP and the functional electrode was obtained with PEA as template,PATP as monomer and Au as bridge linker.After elution of template,the recognition cavity on electrode was achieved.The modified condtions of electrode were optimized and the modified electrode was characterized with SEM.The analytical performance and application of the developed electrochemical sensor were examined in detailed.Under optimum conditions,the LOD was as low as 1.0×10-13 mol/L.The linear relation was ranged from 1.00×10-13 to 1.00×10-9 mol/L with good linearity of 0.996.The recoveries of PEA were from 92.7%to 108.4%under different spiked level of PEA in animal urine and the relative standard deviation(RSD)was below 8%.In this study,two-step fabrication method of ulrasensitive electrochemical sensor has been developed based on MOFs and MIP,and the satisfactory sensitivity,specificity and stability were achieved.