Research On Detection Mechanism And Method Of Benzo(a)pyrene In Edible Oil By SERS

As a necessity of life,the consumption demand of edible oil has been increasing year by year.At present,China’s consumption of edible oil has ranked first in the world,so it is crucial to ensure the safety and quality of edible oil.Edible oil in the production process and food cooking link is very vulnerable to pollution and deterioration.As a strong carcinogen,benzopyrene(Ba P)is very easy to produce in this process.It can accumulate in the human body for a long time,causing death,which seriously affects people’s life,health and safety.Although benzopyrene exists in edible oil at trace level,trace benzopyrene will cause death.According to the national standard,the detection limit of benzo(a)pyrene in edible vegetable oil should be less than or equal to 10μg/kg.At the same time,the main pollution of edible oil comes from the production and processing process,which requires on-site real-time supervision.Therefore,it is required that the benzo(a)pyrene detection method should be fast and sensitive enough to prevent the safety problems caused by the excessive benzo(a)pyrene in edible oil,so as to effectively ensure the safety of edible oil.The pretreatment process of traditional detection methods is complex and the detection time is long,which inevitably causes losses in the extraction and detection of benzo(a)pyrene,thus affecting the rapid detection of trace benzo(a)pyrene.SERS technology has the advantages of high sensitivity and real-time rapid detection,which can effectively solve the above problems.Therefore,this paper uses SERS technology to study the detection of benzo(a)pyrene in edible oil.The specific research contents are as follows:Aiming at the problem of effective adsorption of benzo(a)pyrene on SERS enhanced substrate,and considering the difficulty of binding benzo(a)pyrene with precious metal substrate as a hydrophobic organic molecule with no substituent functional group,it is found that GO has a special adsorption function to effectively adsorb benzo(a)pyrene.Combined with the strong electromagnetic enhancement of precious metal Ag and the chemical selective adsorption of GO,the composite substrate prepared in this paper Ag@GO enhance performance for analysis.Aiming at the problem of time-consuming and laborious screening of optimal conditions for substrate preparation experiment,the optimization selection of enhanced substrate was carried out in combination with simulation before substrate preparation experiment.Considering the difficulty of using SERS technology to detect benzo(a)pyrene trace in edible oil,which is limited by substrate activity,from the perspective of electromagnetic simulation of enhancement mechanism,the best electric field enhancement effect was obtained by analyzing the local electric field strength of Ag shape,size and GO film thickness,and realized construction of Ag@GO composite substrate;From the perspective of chemical simulation of enhancement mechanism,structure optimization and theoretical SERS spectrum simulation of Ag@GO-Ba P molecular system were carried out,and theoretical Ag@GO Raman enhancement effect on Ba P molecule provides theoretical support for substrate preparation experiment and subsequent SERS detection.Aiming at whether the optimal SERS enhanced substrate obtained by simulation can realize the trace detection of benzo(a)pyrene in edible oil,carried out the preparation experiment and characterization analysis of Ag@GO composite substrate were,simplified the pretreatment process of benzo(a)pyrene in edible oil,thus shortening the detection time.Ag@GO was used to detect benzo(a)pyrene in edible oil by SERS,and SERS was evaluated from the aspects of detectability,sensitivity,specificity,repeatability,etc.,which met the detection limit requirements of the national standard.On the premise of maintaining high sensitivity,it could detect benzo(a)pyrene in real time quickly.Compared with the national standard method,it was concluded that the SERS technology was feasible to detect benzo(a)pyrene in edible oil in this paper,and verified the results of theoretical simulation.The method established in this paper can effectively solve the problem of the limitations of the current sampling inspection methods for edible oil quality,providing new research methods for the application of SERS technology in the real-time and rapid detection of oleophilic harmful substances in food safety.