| Amino acids are an indispensable substance in living organisms.Some noN-essential amino acids and their metabolites are related to certain diseases of human beings.Tyrosine and glycine are important noN-essential amino acids in the human body.The abnormal metabolism of these two noN-essential amino acids is related to certain diseases.Studies have found that when liver and kidney diseases,maligna nt tumors and other diseases occur,the metabolism of tyrosine and glycine will be abnormal.Therefore,study to establishe a simple,sensitive and rapid analytical method and apply to the separation and analysis of tyrosine and glycine metabolites in human body fluids,which has important practical significance for the auxiliary diagnosis,treatment and monitoring of certain diseases.In this paper,the related molecula r ly imprinted polymers were prepared and used for the separation and enrichment of tyrosine and glycine metabolites in human body fluids,which combined with ultra-high performance liquid chromatography to construct the new method for analyzing tyrosine and glycine metabolites in human body fluids.The method was used to detect actual samples and have achieved satisfactory results.The main research results are as follows:1.P-hydroxyphenyl acetate molecularly imprinted polymer?PHPAA-MIP?was prepared by precipitation polymerization,which is using P-hydroxyphenylacetic acid as a template molecule,1-vinylimidazole as a functional monomer,trimethylpropa ne triacrylate as a crosslinking agent,N-N azobisisobutyronitrile as an initiator and acetonitrile as a solvent.According to the adsorption kinetics experiment,the adsorption mechanism of PHPAA-MIP was explored and the recognition performance and selection performance of PHPAA-MIP were evaluated.The results showed that PHPAA-MIP had higher selective adsorption properties for p-hydroxyphenyl lactic acid,p-hydroxyphenylacetic acid and p-hydroxyphenylpropionic acid in urine samples.2.A new method for the determination of p-hydroxyphenyl lactic acid,p-hydroxyphenylacetic acid and p-hydroxyphenylpropionic acid in human urine was developed based on molecularly imprinted polymer separation and enrichment-ultra performance liquid chromatography.The urine sample was diluted twice and the inorganic salt was removed by ENVI-C18 column.The target analyte was extracted by PHPAA-MIP and the final desorbed solution was detected by UHPLC-FLD.Under optimized extraction/desorption conditions,a ZORBAX SB-C8 rapid separation column was used with a mobile phase of 50 mmol/L acetic acid-ammonium acetate?pH=5.3?:acetonitrile=95:5?V/V?.Separated at 0.2 mL/min.The fluoresce nce detection wavelength was?ex=277 nm and?em=316 nm.The detection limits and quantitation limits of the three analytes were 8.5×10-3-2.8×10-2 mg/L and 2.8×10-2-9.3×10-2 mg/L,respectively.The recoveries were 75.7.%-110.3%,relative standard deviation is less than 15%.The method has good selectivity and can be used for the simultaneous determination of three tyrosine metabolites in urine.3.N-phenylglycine as the template molecule,acrylamide as the functio na l monomer,trimethylpropane triacrylate as the crosslinking agent,N-N azobisisobutyronitrile as the initiator and acetonitrile as the solvent,molecula r ly imprinted polymer?NPG-MIP?was prepared by precipitation polymerization.The prepared polymer was characterized by various analytical techniques.The adsorption characteristics of the molecularly imprinted polymer were studied.The results showed that NPG-MIP had better affinity than NIP to adsorb the target analyte and the selectivity of the structural analog of the target analyte was poor.The imprinting factor IF=4.7.The material lays the foundation for the separation of NPG from complex samples?urine samples?.4.A new analytical method for the determination of N-phenylglycine in human urine samples by molecularly imprinted polymer separatioN-ultra-high performance liquid chromatography was developed.The urine sample was diluted 20 times and was pretreated with NPG-MIP imprinted polymer.The desorbed solution was detected by UHPLC-DAD.Under optimized extraction/desorption conditions,ZORBAX SB-C18rapid separation column was used with 20 mmol/L sodium dihydrogen phosphate?pH=5.6?:methanol=90:10?V/V?as mobile phase with a flow rate of 0.2 mL/min.The UV detection wavelength was?=239 nm.The linear range of NPG is 0.5-100 mg/L,the detection limit and the limit of quantification are 1.6×10-2 mg/L and 5.5×10-2 mg/L,respectively.The recoveries of the method are higher than 84.7%and the relative standard deviation is less than 11%.This method has high selectivity for the target analyte and provides a methodological basis for further exploring the relations hip between glycine metabolism and cancer. |
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