Preparation And Application Research Of Molecularly Imprinted Polymers Of The Aflatoxin

Aflatoxin is a class of similar structure metabolites with dihydrofuran coumarin.It is mainly produced by fungus such as Aspergillus flavus and Aspergillus parasiticus,occurring in cereal crops such as corn,peanuts and fodder even other products like almonds,figs and milk.AFB,has been designated as Class 1 carcinogens by WHO-IARC in 1993 due to the acute toxicity,carcinogetic and mutagenic.To protect the human health,it is necessary to develop a simple,sensitive,low cost method for aflatoxin detection.In the study,we proposed a novel molecularly imprinted polymers with highly sensitive and selective determination of aflatoxin.The molecularly imprinted polymer?MIP?was prepared by surface sol-gel method using 5,7-dimethoxy coumarin?DMC?which is aflatoxin analogue was chosen as the template,supported ionic liquid as the functional monomer and carrier,tetraethoxysilane?TEOS?as the cross-linker.MIP was characterized by the static adsorption experiments,the kinetic adsorption experiments and Fourier transform infrared spectrometer?FT-IR?.The above results indicated that MIP had been successfully synthesized and had fast mass transfer rate.Second,the MIP was applied as a sorbent in SPE coupled with HPLC-FLD.Under the optimum conditions,the correlation coefficient?R2?with B,,B2,G1,G2 was more than 0.9937,respectively.The method was proposed with LODs?S/N=3?ranged 0.03 from 0.09?g L-1,and RSD?n=9?<9.7%.The selectivity experiments showed the MIP-SPE for aflatoxin was much higher selective adsorption than ochratoxin A and Sterigmatocystin,and this column showed better selectivity for B₁,B₂,G₁,G₂ than M1,M2.Finally,to evaluate the usefulness of the new method,three samples of corn,peanuts and fodder were spiked recovery.When the contents of samples were low?<10?g kg-1?,the recoveries of 4 aflatoxins?B₁,B₂,G₁,G₂?were 77.8%-106.4%?RSD<7.7%?,34.0%-98.9%?RSD<9.3%?,44.3%-89.8%?RSD<7.3%?,24.3%-63.6%?RSD<8.9%?,respectively.Compared with immune-affinity column,MIP-SPE showed better chromatography,better selectivity for B1.To use the advantage of MIP,MIP-SPE can be used to detection of B₁,B₂,G₁,G₂ in samples due to aflatoxin has types and acute toxicity.In summary,MIP-SPE had a series of advantages,such as low cost,experimental operation simply,short time-consuming,high sensitivity and selectivity.Thus,it is suitable for the detection of B₁,B₂,G₁,G₂ in food samples.