The Research And Application Of The Visual Detection Method Of Triadimenol

China is a big producer and exporter of tobacco.In order to control tobacco fungal diseases,improve the yield and quality of tobacco leaves,triazole fungicide is inescapably used in the process of tobacco leaves growing.Due to improper operation and overspray of using triazole fungicide,there may be excessive triazole pesticide residues in tobacco leaves.The residue of triazole fungicide in tobacco leaves pollutes the environment,endangers human health and affects import and export trade of China.Therefore,the rapid and efficient trace analysis of triazole fungicide in tobacco leaves is particularly important.The aim of this paper is to develop fast and visual detection methods for triadimenol in tobacco leaves.The triadimenol in the complex matrix was separated and enriched by Molecularly Imprinted Solid Phase Extraction(MISPE),gold nanoparticles(AuNPs)colorimetric sensor and AuNPs colorimetric gel were used for semi-quantitative or quantitative analysis of the pretreated samples.The main contents of this paper are as follows:1.Preparation and adsorption performance of triadimenol-Molecularly Imprinted Polymers(MIPs).The designing of triadimenol-MIPs imprinting system was based on Density Functional Theory(DFT)under wb97xd/def2 tzvp level,MAA was selected as the optimal functional monomer,with the best ratio 3:1 with the template molecule.On this basis,the triadimenol-MIPs with the average particle size 236 nm was prepared by precipitation polymerization,adsorption time was chosen as 60 min,the kinetic adsorption law of MIPs was accord with kinetic quasi-secondary adsorption,the isothermal adsorption law was accord with the Freundlich adsorption,which belongs to the multilayer adsorption with heterogeneous surface.The triadimenol-MIPs had specific recognition ability of triadimenol;2.Setting up fast and visual detection methods for triadimenol based on AuNPs colorimetric analysis.The AuNPs colorimetric sensor system was optimized so that the triadimenol with the concentration of 0.15-32?mol/L could be detected by a fast and visual semi-quantitative way or a quantitative way under uv-visible spectrophotometer within 6min.The response time of the AuNPs colorimetric gel fortriadimenol was 10 min,and its performance was stable for 20 days without any change in color or uv-visible absorption spectra.The triadimenol with the concentration of 30-180?mol/L could be analyzed in a fast and visual semi-quantitative and a quantitative way.The AuNPs colorimetric gel in this study could solve the problem that the color and spectrum of the AuNPs colorimetric sensor change rapidly as the detection time increased.This colorimetric gel is solid state,which was convenient to be carried and could provide convenience for the detection process.3.AuNPs colorimetric sensor and AuNPs colorimetric gel were used to detect triadimenol in tobacco leaves after pretreatment by MISPE,and the results were compared with UHPLC-MS/MS method.The recovery rates of the three detection methods were 93.574-112.126% for AuNPs colorimetric sensor,101.011-104.471%for AuNPs colorimetric gel and 90.275-104.9% for UHPLC-MS/MS.The RDS of three detection methods were less than 8.430%,6.23% and 3.521% respectively,which met the requirements for the analysis of triadimenol in tobacco leaves.The AuNPs colorimetric gel could improve accuracy,stability and reproducibility of the detection results compared with AuNPs colorimetric sensor.