Efficient Analysis Of Domoic Acid Toxins By Capillary Electrochromatography With POSS-based Hybrid Monolithic Column

Capillary electrochromatography(CEC)with hybrid silica monolithic column possesses of the advantages of rapidly and highly efficient separation of samples,and low reagent consumption,and become a research hotspot in the field of chromatographic microanalysis in recent years.In this paper,the preparation of separation column and the development of separation method are introduced.Based on polyamine modified functionalized stationary phase,the method for the separation of amnestic shellfish toxin by CEC and the analysis of domoic acid is focused and has been developed.The first part is a review.Here,the basic principle and the development of capillary electrochromatography are generalized;the status and applications of monolithic column are summarized;the properties of amnesic shellfish toxin and the research status of its analytical methods are reviewed.Accordingly,the research topics and research schemes of this thesis are proposed.The second part,based on the ring-opening reaction of epoxy-amino groups,the POSS-based hybrid monolithic column is prepared by one-pot polymerization,with butylenediamine BDA,or POSS(POSS-epoxy)grafted with octaglyceryl dimethylsilyl groups and branched poly(ethylene imine)(PEI).Here,the effects of polymer composition on the hybrid monolithic column are surveyed;the structure,permeability and efficiency of the column are studied;the mechanical stability and reproducibility of the hybrid silica monolithic column are investigated,and its chromatographic retention mechanism is explored.Results show that the prepared hybrid monolithic column has merits of good hydrophilicity and good mechanical stability,and it can be applied to the efficient separation and detection of phenolic compounds and benzoate-like compounds.And the prepared hybrid monolithic column provides a kind of functional material with good performance for the follow-up research.In the third part,based on the POSS-PEI monolithic column,the separation of DA from polyamine bonding functionalized stationary phase is investigated in the presence of metal ions.Here,the effects of mobile phase pH,the concentration of KH2PO4 and MgSO4,separation voltage and acetonitrile volume on the retention of DA are investigated with the chelation of Mg2+.Then,the interactions of metal ions of Mg2+,Fe3+,Zn2+and Cu2+ with domoic acid on the stationary phase are investigated.The results showed that there is a clear metal coordination between metal ions and polyamine-bonded functionalized stationary phase and DA respectively.Herein,the separation mode of the hybrid monolithic column based on metal ion exchange chromatography is established.In the fourth part,the separation mode of the hybrid monolithic column is used for the separation and quantitative analysis of DA in shellfish samples.Here,the technical parameters of this separation mode are investigated.Then,fast analysis of domoic acid(DA)in shellfish samples with a detection limit of 0.125 ?g/mL(equivalent to 0.5 ?g/g that less than MRL at 20?g/g)is realized.And,the shellfish extract can be injected without SPE purification,and the recovery rate is at the range of 92.7%-103.9%when the concentration of DA at 4.g/g,20 p,g/g,40 ?g/g,respectively.Above all,the method has the advantages of simple steps,easy operation,short analysis time,minimal sample consumption,and the method can be used for the efficient monitoring of tracing domoic acid in shellfish samples.