Study On Immunolateral Chromatography Detection Method Of Tetracycline And Penicillin Residues In Milk

Since the discovery of antibiotics,it has been widely used in the medical field and can treat a variety of human and animal diseases.Therefore,it has been widely used in animal husbandry and even caused the abuse of antibiotics,resulting in antibiotics originating in animals such as milk,eggs,and pork.The problem of residues in food is getting worse.Therefore,the establishment of a rapid,convenient and sensitive antibiotic residue detection method is of great significance for preventing food safety problems and protecting human health.Therefore,this paper establishes three rapid detection methods based on immunolateral chromatography technology for tetracycline and penicillin antibiotics,which are more serious residues in food:（1）Establish a traditional immunochromatographic test strip detection method for tetracyclineDetection of tetracycline based on specific immunorecognition of antigen and antibody and lateral capillary force.This experiment also optimized the experimental conditions such as the amount of tetracycline labeled antibody,the amount of K₂CO₃added,the type of blocking agent and the size of the gold nanoparticles.Under the final optimized key experimental parameters,the detection sensitivity of tetracycline observed by the naked eye was 10 ppb,and the linear relationship of the standard curve established between the detected concentration of 0.2-10 ppb is good.The optimized experimental parameters are also applicable to the detection of actual samples of tetracycline milk,and are not affected by the complex components in the milk matrix.（2）Establish a test method for pre-incubation sensitized immunochromatographic test strips of tetracyclineBased on the traditional immunochromatographic test paper,it is improved,giving up the use of gold label pads,adopting the method of directly incubating the target and the gold label antibody in advance,and enhancing the binding efficiency of the labeled antibody and the target to make the detection sensitivity significant improve.In this experiment,conditions such as the amount of sensitized antibody conjugated,the amount of K₂CO₃ added during conjugation,the amount of gold standard antibody complex solution and other conditions were optimized to determine the best experimental parameters.Under the optimal experimental conditions,the minimum detection limit for tetracycline is 2 ppb,the sensitivity is 5 times higher than that of traditional test strips,and the linear relationship of the standard curve established between the detection concentration of 0.05-2 ppb is good.The optimized experimental parameters are also applicable to the detection of actual samples of tetracycline milk,and have great application potential in the field of rapid detection of antibiotic residues.（3）Establishment of a dual detection method for tetracycline and penicillin-sensitized immunolateral chromatography test stripsBased on the pre-incubation sensitized immunochromatographic test paper,the dual detection of tetracycline and penicillin was performed at the same time.This experiment also optimized the experimental conditions such as the amount of penicillin conjugated antibody and the amount of K₂CO₃ added.Under the most suitable experimental parameters,the minimum detection limits of tetracycline and penicillin were 2 ppb,and the linear relationship between the two standard curves established between the detection concentration of 0.05-2 ppb is good.Through the addition recovery experiment,it is found that this method is also suitable for the simultaneous detection of residual tetracycline and penicillin in milk samples,and has great potential in the field of multi-component detection of antibiotic residues.