| With the improvement of people's living standards,more and more animal foods appear on people's tables.In order to increase the output of animal products,unscrupulous businessmen often add growth-promoting drugs in the feeding and production of animals.As the food chain accumulates,these banned veterinary drugs will seriously damage human health,and the ensuing problems of food safety are endless.The rapid and sensitive detection of banned veterinary drugs is an important means of prevention and control of food safety,and is of great significance for ensuring food safety and protecting public health.Estrogen and?-agonist drugs are two more common types of illegally added growth-promoting veterinary drugs,17?-estradiol(17?-E2)and clenbuterol are representative substances of these two types of veterinary drugs.So the detection of these two veterinary drugs is of great significance for the prevention and control of food safety.Currently,instrumental analysis methods and rapid detection methods are the main detection methods for these two drugs.The instrument analysis method mainly uses liquid chromatography and other large-scale precision instruments for analysis and detection.It has the disadvantages of higher cost,more complicated pre-treatment process,and longer detection time.It is not suitable for rapid on-site detection of animal residues.However,many current rapid detection methods often have disadvantages such as low detection sensitivity,complicated operation process,and poor detection stability.This article intends to establish two rapid detection methods:17?-E2 immunodiafiltration test strip detection method based on the photothermal effect of black phosphorus(BP)nanomaterials and clenbuterol immunofiltration test strip based on the photothermal effect of black phosphorus-Au nanosheets(BP-Au NSs).In the follow-up operation,the detection performance of the two methods established was evaluated,proving that they can achieve high specificity and high sensitivity detection of 17?-E2 and clenbuterol hydrochloride,which can be applied to the actual samples of animal residues Detection.The above method is relatively simple in operation,does not require the use of relatively large or expensive instruments and equipment,has short detection time and low cost,and can be applied to the rapid detection of on-site samples for food safety supervision.This paper mainly includes four parts,as follows:In the second chapter,a 17?-E2 immunodiafiltration test strip detection method based on the photothermal effect of BP nanomaterials is established.The good photothermal conversion efficiency of two-dimensional black phosphorus nanosheets(BPs)is used to achieve fast and sensitive detection.Compared with the traditional test strip colorimetric method,the detection sensitivity is greatly improved.The introduction mainly introduces the main hazards of 17?-E2 and Clenbuterol and the research progress of current detection methods,clarifies the significance of establishing a new rapid detection method,and summarizes the current application of photothermal effects and the research used to establish detection methods.Several widely used photothermal nanomaterials were also introduced.In this method,the coating antigen of 17?-E2 is first coated on the surface of the nitrocellulose membrane,and then sealed.BPs were coupled with 17?-E2 antibody as a recognition probe,and the liquid to be tested was added to the probe solution.After incubation,it was added dropwise to the detection area of the diafiltration test strip.The 17?-E2 in the test solution will compete with the antigen on the membrane to bind the antibody binding site.The higher the concentration of 17?-E2 in the test solution,the fewer the probes bound on the membrane and the lighter the color.After constant temperature drying,808 nm laser is used to irradiate the area to be measured under optimal conditions,and a linear relationship is established with the temperature change value and the concentration of 17?-E2 to achieve quantitative detection of 17?-E2.The actual detection effect of this method is verified in this paper,and its minimum detection limit can reach 0.104 ng·m L-1,the recovery rate of addition in tap water is between 87.8%?101.2%,and the recovery rate of addition in milk is 93.1%?105.8%,and the recovery rate was compared with the standard method of high performance liquid chromatography.The correlation coefficient was 0.9371,which was close to the detection level of liquid chromatography,and it could meet the needs of actual detection.The third chapter proposes to establish a detection method of clenbuterol hydrochloride immunodiafiltration test strip based on the photothermal effect of BP-Au NSs.Specific detection.Compared with BPs,the photothermal conversion efficiency of composite materials is higher,and a relatively small dose can reach a higher dose of photothermal temperature of a single material.More excellent photothermal performance indicates a more sensitive detection level.In this method,the clenbuterol hydrochloride antigen was first coated on the surface of the nitrocellulose membrane,the background on the membrane was minimized by changing the type and concentration of the blocking solution,and then the conditions such as laser irradiation time,solution p H,antibody addition amount optimize.Under the best conditions,the linear relationship between the concentration of clenbuterol standard solution and the temperature change value was determined,and the specificity of the method was verified.Follow up the determination of the added recovery in milk and fresh pork,and finally compared with the detection limits of other reported clenbuterol hydrochloride detection methods to determine their detection performance,and then used in the field of clenbuterol hydrochloride for rapid and sensitive on-site detection.Chapter four summarizes and evaluates the 17?-E2 detection method based on the photothermal effect of BPs,proving that this method can be used for rapid on-site detection of actual samples,with low detection sensitivity,good method stability,and low cost and specificity.It has the advantages of strong,simple operation process,short detection time,and no need of large instruments and equipment.It can be applied to the rapid detection of veterinary drug residues on site.The detection method of clenbuterol hydrochloride based on the photothermal effect of BP-Au NSs was preliminarily verified,followed by condition optimization and establishment of a standard curve. |
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