Studies On Chiral Separation Of Enantiomers Of Amino Acid By Constituting Chiral Caves With Surface-Molecular Imprinting Technique

The basic unit amino acids that make up the protein play a very important role in the regulation and metabolism of the body in the living body in a free manner.Therefore,the study of amino acid resolution has broad application prospects.There have been a lot of researches on amino acid resolution,but there are some shortcomings in achieving efficient,large-scale,and low-cost resolution of amino acids.Design and development Identifying a high separation rate,low cost,and high selectivity splitting method is a challenging problem.In this study,surface molecular imprinting techniques were applied and L-glutamic acid surface imprinted materials MIP-PDAC/PSA and MIP-PSSS/PSA with good specific selection properties were prepared.First,the raw material PSA is placed in N,N-dimethylformamide?DMF?to be immersed to activate the amino group on the surface of the PSA,and the surface of the PSA is grafted by a radical.SSS)was grafted onto the surface of PSA to prepare grafted particles PSSS/PSA.The grafted polymer PSSS/PSA was characterized by infrared spectroscopy.The effects of solvent,temperature,amount of initiator and reaction time on the grafting degree during the preparation process were studied.Sexual characteristics,using the titration method to detect the grafting rate of SSS,while using the hydrogen bonding on the grafted polymer PSSS/PSA chain and the hydrogen bonding force on the glutamic acid molecule,the adsorption of glutamic acid by PSSS/PSA is realized.The optimal adsorption conditions between polymer PSSS/PSA and glutamic acid molecules were investigated by exploring various conditions in the adsorption process.The results showed that 42 mL of solvent?V methanol:V water=5:2?was added to the modified PSA of 0.2000 g,the mass fraction was 1.2%of the total solution,and the initiator ammonium persulfate accounted for 0.8%of the monomer mass fraction.When the reaction temperature is 50?and the reaction time is 8 h,functional particles with a maximum grafting degree of 230.27 mg/g can be obtained.At a temperature of 30?,the adsorption time is t=3 h,and at pH=4,the PSSS/PSA is L-glutamic acid.The maximum adsorption capacity is 120 mg/g.The raw material PSA is placed in N,N-dimethylformamide?DMF?to be immersed to activate the amino group on the surface of the PSA,and the monomer is acryloyloxyethyltrimethyl group by radical-initiated graft polymerization.Ammonium chloride?DAC?was grafted onto the surface of the PSA to prepare grafted particles PDAC/PSA.The grafted polymer PDAC/PSA was characterized by infrared spectroscopy.The effects of solvent,temperature,amount of initiator and reaction time on the grafting degree during the preparation process were studied.Sexual characteristics,using titration method to detect the grafting rate of DAC,while using the hydrogen bonding on the graft polymer PDAC/PSA chain and the hydrogen bonding force and electrostatic interaction on the glutamic acid molecule,realize PDAC/PSA to glutamic acid The adsorption,through the exploration of various conditions in the adsorption process,investigated the optimal adsorption conditions between the polymer PDAC/PSA and glutamic acid molecules.The results showed that the optimum preparation conditions were as follows:adding 0.2000 g of modified PSA to the solvent,adding 40 mL of ethanol,the monomer mass fraction was 6%of the total solution,the initiator ammonium persulfate was 1.2%,and the reaction temperature was 50?.At 8h,functional particles with a maximum grafting degree of 433.5mg/g can be obtained.At a temperature of 30?,the adsorption time is t=2.5 h,and the maximum adsorption amount of PDAC/PSA to L-glutamic acid is 141.3 at pH=4.mg/g.The graft polymer macromolecular chain PSSS can form a strong hydrogen bond interaction with the L-glutamic acid molecule.Based on this,the surface imprinted material MIP-PSSS/PSA was prepared in aqueous medium using SSS as a functional monomer.Through the surface imprinting technique of"graft polymerization and cross-linking imprinting"established by our research group,L-glutamic acid is used as a template molecule,and N,N-methylenebisacrylamide?MBA?is used as a crosslinking agent.The surface imprinting of L-glutamic acid molecule was successfully carried out under the action of ammonium persulfate.The L-glutamic acid surface imprinted material MIP-PSSS/PSA was applied to the template molecule by static adsorption and dynamic adsorption.The binding ability and selection recognition characteristics,as well as the resolution of its chiral glutamic acid.The results show that the L-glutamic acid surface imprinted material MIP-PSSS/PSA has good recognition selectivity and enantiomeric resolution:compared with D-glutamic acid,imprinted material MIP-PSSS/PSA vs.L-Valley The selectivity coefficient k of the acid is4.65.In addition,the main factors affecting the selectivity and chiral resolution of the imprinted material are temperature,crosslinker MBA and template molecule dosage:temperature 30?,crosslinker MBA and The ratio of the mass of the monomer SSS is 1:5,and the ratio of the mass of the L-glutamic acid to the monomer SSS is 1:250,which shows the racemic solution of the L-Glu single enantiomer imprinted material to Glu.Has good split performance.The graft polymer macromolecular chain PDAC can generate hydrogen bonding and electrostatic interaction with glutamic acid molecules.Based on this,this study used DAC as a functional monomer to prepare L-glutamic acid molecular surface imprinted material MIP-PDAC/PSA in ethanol and water?V₁:V₂=3:7?solution.DAC was used as a functional monomer,L-glutamic acid was used as a template molecule,and MBA was a cross-linking agent.Under the action of ammonium persulfate,the surface imprinting of L-glutamic acid molecule was successfully carried out to prepare L-glutamine.Acid molecular surface imprinted material MIP-PDAC/PSA;using static adsorption and dynamic adsorption methods,the binding and recognition characteristics of surface imprinted material MIP-PDAC/PSA to glutamic acid and its chiral glutamic acid decomposing were investigated.Performance.The results showed that the L-glutamic acid surface imprinting material MIP-PDAC/PSA has specific recognition selectivity and enantiomeric resolution for L-glutamic acid:compared with D-glutamic acid,imprinted material MIP-PDAC The selectivity coefficient of/PSA for L-glutamic acid is 5.92;in addition,the main factors affecting the selectivity and chiral resolution of imprinted materials are temperature,crosslinker MBA and template molecule dosage:at a temperature of 30?The ratio of the crosslinking agent MBA to the monomer DAC mass is 1:40,and the ratio of the L-glutamic acid to the monomer DAC mass ratio is1:250,which shows the L-Glu single enantiomeric imprinting material to Glu.The racemic solution has good resolution properties.