Optimization And Application Of Detection Techniques For Veterinary Drug Residues In Egg Agricultural Products

Egg agricultural products are the main source of protein in the dietary structure of Chinese residents,which occupies a large proportion in the daily diet.Therefore,the detection of veterinary drug residues in egg agricultural products is an important link to ensure the daily diet safety of residents.In view of the important position of egg agricultural products in people’s dietary structure,in order to accelerate the rapid development of breeding industry,and to ensure the healthy development of breeding industry,veterinary drugs are widely used.The problem of veterinary drug residues in egg agricultural products has also aroused wide concern in the country and even the world.At present,for different types of veterinary drug residues in egg agricultural products,the relevant national standards have adopted different methods for detection,resulting in shortcomings such as long detection cycle,high detection costs,and low detection efficiency.In this study,the detection technology of veterinary drug residues in egg agricultural products will be optimized,a method for simultaneous determination of multiple veterinary drug residues by high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)was established.In this study,egg was taken as the main research object,and a high-speed and efficient quantitative method was established for simultaneous detection of 30 veterinary drug residues including quinolones,sulfanilamide,nitroimidazoles,amantadines and chloramphenicol,which were commonly found in egg agricultural products.The feasibility of the method was evaluated through detection analysis in 100 batches of egg agricultural products.The scalability of the method is also evaluated.The results are as follows:(1)In this study,the optimal mass spectrometry detection conditions and ion parameters of 30 veterinary drug residues and internal standards were determined through the optimization of instrument parameters.1% formic acid was used as the aqueous phase and acetonitrile as the organic phase.After running the elution procedure for 13 min,the test liquid was determined.The quantitative method of quinolones,chloramphenicol and amantadines was established by internal standard isotope method,and the quantitative method of nitroimidazoles and sulfonamides was established by external standard method;(2)Through optimizing the extraction method,this study investigated the effects of extraction solvent,extraction method,extraction times,and purification method on the recovery rate of the target substance,and the optimal extraction scheme of this study was determined as: Anhydrous sodium sulfate was used to remove water from eggs as a pre-treatment.The homogeneous extraction method was used for two times of extraction.The first extraction solvent was 3m L 0.1mol/L EDTA-2Na aqueous solution and 7m L acetonitrile,and the second extraction solvent was 3m L ethyl acetate and 7m L acetonitrile;The extracts were combined twice,concentrated by nitrogen blowing and restored to 5 m L with 1% formic acid aqueous solution;The purification methods were C18+PSA powder and n-hexane,and then solid phase extraction column was used to collect eluent,nitrogen was blown to nearly dry,and 1 m L 1% formic acid aqueous solution was used for constant volume filtration and 0.2μm filter membrane;(3)This study verified the established detection method and good linear relationship of30 veterinary drugs was observed within the linear range of 1 ～ 20ng/m L or 5 ～ 100ng/m L,and the correlation coefficient R was greater than 0.998.The relative standard deviation of the precision of 30 veterinary drugs was 0.63% ～ 11.11%,the recovery rate for spiking was62.9% ～ 119.3%,and the relative standard deviation was 0.26% ～ 9.46%,the detection limit of this method was 0.09μg/kg ～ 0.96 μg/kg.At the same time,the quality control samples were measured and the test results were within the range of characteristic values;(4)The method was applied to actual detection.Of the 100 batches of samples,4batches of samples detected traces of a drug in 30 veterinary drugs;of which the content of metronidazole in 2 batches was detected to be lower than the detection limit according to relevant national standards,and the test results were used as risk warnings;The remaining 2batches of products are unqualified samples,and the relative error between the test results and the relevant national standards is less than 5%;(5)At the same time,the scalability of this research method is also explored,and it can be applied to pork and aquatic products.The detected veterinary drugs were enrofloxacin and sulfonamides,of which the detection rate of pork was 20% and the detection rate of aquatic products was 30%.Compared with the detection results of relevant national standards,the relative errors were within 15%,and the unqualified rate of aquatic products was 10%.Therefore,this method is also suitable for the detection of 30 veterinary drugs residues in pork and aquatic products.In summary,it can be seen that,this method is suitable for the detection and quantitative analysis of 30 veterinary drug residues in egg agricultural products,pork,and aquatic products.It has the advantages of high speed,high efficiency and simultaneous detection.It provides a basis for daily risk monitoring of agricultural products,and technical support for national supervision and sampling of egg agricultural products.It also helps consumers correctly understand the risks of veterinary drug residues,eliminate unnecessary panic,and scientifically guide consumer purchasing behavior and standardize the production and operation activities of enterprises.