The SPR Detection Of Salmonella Enteritidis In Food Using Aptamers As Recongnition Elements

Nowadays, how to make the food safer and healthier becomes the main topic in the society. In food safety problems, food-borne diseases show a rising trend, and in food-borne diseases, Salmonella enteritidis mainly cause gastroenteritis of animals and food poisoning of human.Salmonella enteritidis is an important human and zoonotic pathogens. In recent years, the research on Salmonella in food has focused on Salmonella typhimurium, while Salmonella enteritidis,which also has lethal effect, has been neglected. In order to overcome the shortcomings of the traditional detection methods such as cumbersome and time consuming, it is necessary to establish a fast and accurate detection method.In this experiment, a rapid detection method for Salmonella enteritidis was established.The plasma resonance resonance biosensor (SPR) was used as the detection instrument to provide a rapid, accurate, non-destructive, non-marking and simple operation experiment.Moreover, the immunological recognition element selected in this experiment is aptamer,which is more specific than the antibody for immunological recognition. The aptamer has better stability and specificity than the antibody, and its molecular weight is smaller, the dosage is more Less, and it is more cheaper.The experimental results show that the growth curve of Salmonella enteritidis showed a concentration of 2.1×108 cfu/mL at 4 hours.The best flow rate was 5 μL/min in the experimental, the best concentration of the aptamers was 180mM,the best regenerating solution was the 20 mM NaOH solution,and the most common pathogens in food were Escherichia coli,Staphylococcus aureus,Listeria monocytogenes had almost no cross-reactivity, and a more accurate standard curve of Salmonella enteritidis and SPR signal was established.The detection limit was 2 cfu/mL.We tested samples of chicken,pork, shrimp and fish purchased from supennarkets.The results of plate count proved the reliability and application value of the method and results. The method has the advantages of short time,low detection limit and easy operation, and it can be used for a large number of food samples.