Separation And Purification Of Bilobalide By Molecular Imprinted Solid Phase Extraction And Antidepressant Study

Bilobalide(BB)is one of the unique substances in Ginkgo biloba,which can protect nervous system,lower blood pressure and fight fatigue,however,there are few studies on its antidepressant effects,and the mechanism of action is still unclear.The acquisition of high purity for BB is conducive to explore the antidepressant activity to improve the application value of health care and treatment.There are many methods for separation and purification of BB,but all of them exhibit some deficiencies.At present,the realization of high selectivity and high efficiency for separation of BB are the hotspots of research.In this study,BB molecularly imprinted polymer(BBMIPs)were prepared by bulk polymerization based on the theoretical guidance of computer simulation technology,then the MIPs were systematically characterized.Meanwhile,the adsorption properties were investigated via various aspects.To improve the adsorption performance and selectivity of the polymers,the MWCNTs/ZIF-67@MIPs were successfully synthesized by surface molecular imprinting(SMIT)technique using MWCNTs/ZIF-67 as the support matrix.Separation and purification of BB from the actual samples was achieved by molecular imprinted solid phase extraction(MISPE)using the polymers prepared by the two methods were used as sorbents,respectively.Finally,chronic unpredictable mild stimulation(CUMS)method was employed to replicate the depression model of mice to investigate the effect of BB on the depressive behavior.The main research findings were summarized as follows:(1)Methacrylamide(MAM)was selected as the appropriate monomer by Gaussian software simulation;Optimization results of preparation process obtained by single factor experiments: trimethylpropane triacrylate(TMPTA)as crosslinker,acetonitrile as solvent,the molar ratio among the BB,MAM and TMPTA was 1:4:15;FT-IR,SEM,TGA were used to characterize the polymers.The equilibrium adsorption concentration and time were 0.6 mg/m L and 5 h,respectively;The imprinting factor of MIPs for BB reached1.95,indicating the selectivity was good;The recovery rate of MIPs was 74.3% after used repeatly for 5 times.(2)MWCNTs/ZIF-67@MIPs were grafted on the surface of MWCNTs/ZIF-67.The preparation process was optimized: MAM and 4-VBA as bifunctional monomers,acetonitrile and [BMIM] BF4 as the mixed solvent,TMPTAas crosslinker,the molar ratio among the template,monomer and the crosslinker was 1:4:20;SEM,FT-IR,XRD and TGA indicated that the polymers were grafted successfully;The equilibrium adsorption concentration and time were 0.8 mg/m L and 4h,respectively.Compared with BBMIPs,the specificity and adsorption quantity had significantly improved.(3)The SPE column was filled with two kinds of polymers for the separation and purification of BB from the actual sample after the extraction conditions of MISPE were optimized.The experimental results showed that the separation effect on BB for MWCNTs/ZIF-67@MIPs was than BBMIPs(4)The mitigating effect of BB on depressive behavior was explored based on the mouse depression model by CUMS.Behavioral indexes,content changes of monoamine transmitters in brain all showed that the depression model was successfully constructed,and BB could slow down significantly the depressive behavior in mice.