Preparation Of Chiral Molecularly Imprinted Polymers And Electrospinning Fibers

Molecularly imprinted polymer is a kind of high-molecular polymer that can make the spatial structure matching with the target moleculeis at the junction.Due to the ability to identify target moleculeis,it has strong specificity and has been widely used in the separation of chiral drugs.Electrospinning fibers have advantages of controllable structure,easy operation,and the formed fibers have a very small diameter and a relatively large specific surface area.They can be used as a carrier for enzyme immobilization.At present,the electrospinning fibers of immobilized enzyme are mainly applied in the fields of biomedicine,sensors and catalysis.The main work of this paper is as follows:?1?L-mandelic acid imprinted polymer was prepared by the method of surface imprinting using the aminated silica gel as carrier.The template molecule and functional monomer are L-mandelic acid and acrylamide,respectively.The polymers were characterized and analyzed by scanning electron microscopy,infrared spectroscopy and thermal analysis etc.The adsorption properties of imprinted materials were also studied.The results show that the imprinted polymer has been successfully grafted onto the surface of the silica gel.From the scanning electron microscope image,it can be seen that the surface of amino silica gel has a layer of hemispherical material.When the concentration of L-mandelic acid solution was140mg/L,the adsorption amounts of SiO₂-APTES-MIP and SiO₂-APTES-NIP tended to be in equilibrium,and the adsorption capacities were 4.03mg/g and 1.62mg/g,respectively.It indicates that the SiO₂-APTES-MIP has an increase in the amount of adsorption due to the existence of pores with identification performance.It also shows that the imprinted polymer material has better reusability.?2?L-mandelic acid imprinted polymer was prepared by the method of surface imprinting using the alkylated silica gel as carrier.The template molecule and functional monomer are L-mandelic acid and acrylamide,respectively.The polymers were characterized and analyzed by ESEM,IR,nitrogen adsorption and desorption etc,and the adsorption properties of the polymer materials were studied.The results show that the imprinted polymer has been successfully grafted onto the urface of the silica gel.From the image of the scanning electron microscope,it is more intuitive to see that the surface of the alkenyl-ized silica gel has a layer of hemispherical material,but it is easy to form a big block.When the reaction time is 140 minutes,the adsorption capacity of SiO₂-VIES-MIP,SiO₂-VIES-NIP and MIP is 1.82mg/g,0.93mg/g and0.63mg/g,respectively.Compared with SiO₂-APTES-MIP,the adsorption capacity of these polymers are relatively small.?3?A type of nanofiber membrane of a polyvinyl butyral?PVB?/op-10/lipase was prepared using electrostatic spinning technology.The effects of voltage and emulsifier on the morphology of immobilized lipase PVB nanofibers membrane were investigated.The relative activity of immobilized lipase and free lipase was discussed under different pH,voltages and diftemperature and storage time.The results of ESEM indicate that the microscopic morphology of PVB/op-10/lipase membrane spun under 14Kv of voltages,10%wt concentration of emulsifier?relative to the amount of PVB?and 10cm of the the distance from the receiver to the needlepoint is uniform.Compared with the free enzyme,it has showed that the immobilized enzyme has better temperature-resistant and better storage stability.After repeated 10 times,the relative activity is about 65%.The esterification rate of lauric acid with lauryl alcohol catalyzed by immobilized lipase can get to 72%after 20 hours of reaction.While the reaction of lauric acid with lauryl alcohol catalyzed by free lipase can not occur.