Rapid Detection Of Four Aflatoxins Based On Molecularly Imprinted Polymers

Aflatoxin(AFT)is a group of fungal toxins produced in certain strains of Aspergillus flavus and Aspergillus parasiticus,which is widely found in soil,animals and plants,various nuts,cereals,milk,edible oil and other products in nature.Therefore,the detection method of ultra-measured and trace aflatoxin in food has attracted great attention.Due to the complex substrates of agricult ural products samples and the extremely low content and limit of aflatoxin,the highly efficient and specific sample pretreatment technology is the key to the highly sensitive and accurate detection of aflatoxin.Molecularly Imprinted Polymerization(MIT)is a bionic technology with specificity and selectivity similar to biological receptors,with significant advantages of durability and low cost under environmental conditions.Traditional yellow aspergillus toxin detection method often requires a large-scale instruments,lead to detection of human resources cost is higher,a wide range of detection of the contradiction between the demand and advanced testing equipment has inspired such as surface enhanced Raman scattering technique used(SERS)and other small fast instrumentation development,under the condition of this study is based on the above conditions:1.Based on the virtual template molecular imprinting technique,molecularly imprinted polymers with class-specific adsorption to Aspergillus flavus B1,B2,G1 and G2 were prepared using precipitation polymerisation using 5,7-dimethoxycoumarin as a virtual template.The surface morphology was characterised by scanning electron microscopy and other technical means,demonstrating that the imprinted polymers(MIP)were sparse and porous.The adsorption capacity was investigated using dynamic and static adsorption tests with a maximum adsorption capacity of 14840?g/kg.The imprinting factor IF ranged from 2.34-4.9.The class-specific recognition of the four aflatoxins by the imprinted polymer was demonstrated by adsorption tests on a selection of two additional mycotoxic properties.2.A specific molecularly imprinted solid-phase extraction(SPE)column was prepared using a synthetic imprinted polymer as a filler to adsorb four aflatoxins.The method showed good linearity in the ranges of 1?g/kg-100?g/kg and 0.1?g/kg-50?g/kg with the correlation coefficients(R2)greater than 0.9998.The spiked recoveries of aflatoxins in the samples ranged from 81.7%to 100.2%at different spiked levels with the relative standard deviations(RSDs)less than 3.4%.RSD)was less than 3.4%.The method proved to have good recovery and reliable stability.3.For the rapid detection of aflatoxin B1 based on surface-enhanced Raman scattering(SERS)technique,seven SERS-enhanced substrates were first synthesized.The SERS signal enhancement effect of aflatoxin B1 was achieved by selecting 1.2 m L of colloidal gold synthesized by reducing chloroauric acid with sodium citrate as the SERS-enhanced substrate.The final Au NPs system was subjected to 7 s signal acquisition at 100%power with a 785 nm laser,with its characteristic peak at 1263.9cm-1 and a good 0.001 mg/kg-5 mg/kg range log-linear relationship with a correlation coefficient(R~2=09868).