Study On Rapid Detection Of T-2 Toxin In Food By Photonic Crystal Sensing Technology

Objective T-2 toxin is very harmful to human body,and its physical and chemical properties are quite stable.Eating foods infected with T-2 toxin is harmful to human health and may even cause triple effects.Therefore,strengthening the screening and monitoring of T-2 poisons is a research focus in the future.In recent years,the detection of mycotoxins still relies on large instruments.These technologies have high sensitivity and specificity.However,large-scale instruments are expensive,require professional manpower,and generally detect pure samples,making the promotion of these technologies difficult.The photonic crystal(PC)is easy to operate in the detection process and can express the advantages of the response signal without adding color reagents.It is an excellent sensing material that can be used for detection,and it shows particularly dazzling potential in rapid detection.In this study,PC was used as the sensing platform,T-2 toxin was used as the detection analyte,and the nucleic acid aptamer was used as the recognition element,a new method for detecting mycotoxins was explored,and a fast,simple,and highly sensitive T-2 toxin was established.analytical skills.Methods: The statistically optimized key experi mental conditions were used to synthesize monodisperse and uniformly-size d silica(Si O2)microspheres.230 nm Si O2 microspheres were selected as the precursors for photonic crystals.Reduced to gold nanoparticles(Au NPs).The surfac e of Si O2 microspheres was modified by amino groups.The N-Au effect of amino groups and Au NPs was used to modify Au NPs on Si O2 microspheres,and the modi fied products were prepared as PC materials for surface functionalization by vertic al deposition self-assembly.The 5 'end of the T-2 toxin aptamer modified the sulfhy dryl group to renaturate the aptamer.The aptamer and the gold nanoparticles were bo und to the surface of the Si O2 microsphere through the binding of Au-S.As a recogniti on element,a target toxin is specifically recognized.When T-2 toxin is present,it will bind to the aptamer,the spatial configuration of the aptamer and the spacing of the P C lattice will change,which will cause the periodic changes of the photonic crystal,the diffraction peaks will drop,and readable opticswill be produced.Signal to achieve the purpose of detection.Use known detection methods to perform sampling and actual sample detection,and perform statistical analysis.Results: The best experimental conditions for synthesizing Si O2 microspheres were obtained by orthogonal design.Si O2 microspheres with uniform particle size and regular shape were successfully prepared.The particle size of microspheres was separated by different speeds of the centrifuge.The particle size of the obtained Si O2 microspheres is 230 nm;Au NPs with a uniform particle size of 5 to 10 nm are obtained by the THPC reduction method;the surface of the microspheres is modified by ATPES to achieve uniform growth of Au NPs on the surface of the microspheres,and the products are stacked into Three-dimensional opal is the most densely packed PC(3D-OCP-PC);an aptamer that can specifically recognize the T-2 toxin is connected to the PC through gold nanoparticles as a medium.When the analyte is added,the T-2 toxin aptamer on the microspheres can effectively capture the analyte,so that the structure of the PC is changed,the difference in refractive index is displayed,and the intensity of the diffraction peak is also changed.Finally,it was shown that the intensity of the diffraction peak of PC gradually decreased with the increase of T-2 toxin concentration during the detection process.The linear range is 1 × 10-2ng / m L ? 1 × 103 ng / m L,and the detection limit LOD = 4.3 × 10-3ng /m L.Comparing the statistical guidance methods,it is concluded that the two methods are consistent with the enzyme-linked immunosorbent assay(ELISA)in detecting T-2 toxins in actual samples(F = 0.045,P> 0.05),and This method has higher sensitivity and wider detection range.Conclusion: This study establishes a label-free rapid detection method based on photonic crystal sensing materials,further expanding the application field of photonic crystals.The statistical analysis and comparison system and the complete method comparison further verify that the method is suitable for the rapid detection of T-2 toxin.The material matrix of the experimental method is a 24-well microplate,which has the advantages of high effective utilization rate and can significantly improve the detection efficiency.