Study Of Improved Immunechromatographic Lateral Flow Strip For Accurate Detection Of Aflatoxin B1

Aflatoxin B1 is a toxin produced by Aspergillus flavus that is often found in moldy agricultural products.It is extremely toxic and is sixty-eight times more toxic than arsenic.Meanwhile,it can cause acute diseases,such as diarrhea,liver damage,and even death in severe cases if you consume more than a certain amount of aflatoxin B1.Thus the research on rapid detection of aflatoxin B1 in agricultural products is of great significance for maintaining world food safety and human health.This article focuses on the following three aspects:(1)Establishment of aflatoxin B1 classical immunochromatographic detection technologyThe classical method of immunological lateral chromatography is based on the immunological recognition of antigen-antibody and the principle of competition method.First,colloidal gold was used as a marker under visible light for color development.The aflatoxin B1 antibody was labeled with electrostatic adsorption on the surface of colloidal gold.The color of the C/T line was observed by the naked eye to determine whether the colloidal gold-labeled antibody bound to the antigen on the T line or the goat anti-mouse secondary antibody on the C line to analyze the content of aflatoxin B1 in the sample and perform quantitative analysis.In the experiment,important parameters were optimized.Under the best experimental conditions,the detection was completed within 5 minutes,the sensitivity reached 0.5μg/L,and it showed good linearity in the range of 0.1 to 5μg/L(R~2=0.9872).This technology has strong repeatability,high stability,and very high specificity,which can effectively detect the Aflatoxin B1.(2)Establishment of improved immunochromatographic detection technology for aflatoxin B1In this study,a pre-incubation method was introduced into the traditional gold nanoparticle immune lateral chromatography test strip.The antibody and colloidal gold conjugate were directly pre-incubated with the sample to be tested instead of the traditional label pad.The Freeze-dried storage conditions,process parameters,and freeze-dried volume was optimized based on the feasibility study to obtain the best experimental protocol,and the specificity and sensitivity of aflatoxin pre-incubation test strips were tested.The improved immunochromatographic technology used a pre-incubation method to achieve ultra-sensitive detection of aflatoxin B1 in five minutes.Its visual detection sensitivity was 0.05μg/L,which is ten times higher than the traditional method.It also had extremely strong linearity,the linear range was 0.01～0.5μg/L(R~2=0.9861),which can be used for ultra-sensitive detection of samples in complex environments.(3)Establishment of ultrasensitive immunolateral lateral chromatography technology of aflatoxin B1 in teaThere was a serious impact on the rapid detection of aflatoxin B1 in tea due to the presence of a variety of matrices.In this study,the effects of tea polyphenols,in tea were first discussed,and then the effects of the matrix were reduced by the dilution effect.More stringent sensitivity was required,thus an improved immunolateral lateral chromatography technology was applied analysis method to achieve accurate detection in complex samples.Meanwhile resullts showed an extremely strong linearity basically consistent with the standard sample:0.01～0.5μg/L(R~2=0.9741).