微滴式数字聚合酶链式反应定量检测食品中金黄色葡萄球菌方法的研究

目的 建立微滴数字聚合酶链式反应(ddPCR)快速定量检测食品中金黄色葡萄球菌的方法.方法 以金黄色葡萄球菌nu基因为靶序列,筛选出同时适用于实时荧光定量PCR(qPCR)和微滴数字PCR(ddPCR)的引物探针,建立食品中金黄色葡萄球菌ddPCR快速定量检测方法,并对该方法进行特异性、灵敏度、准确性和重复性实验.结果...

Detection of Staphylococcus aureus in food by droplet digital polymerase chain reaction

Objective To establish a new quantitative accuracy method for detection of Staphylococcus aureus in food by droplet digital polymerase chain reaction PCR polymerase chain reaction (ddPCR). Methods A pair of primers and probe for both qPCR and ddPCR was selected according to the single copy gene of nuc in Staphylococcus aureus. The specificity, sensitivity, accuracy and repeatability of this method were analyzed. Results The limit of detection (LOD) and limit of quantitation (LOQ) of ddPCR method were determined to be 110 CFU/mL by gradient dilution of pure culture of Staphylococcus aureus. The LOQ of ddPCR was 1 000 CFU/g in the artificial contaminated experiment, and the maximum deviation of detection result of four spiked addition levels was 4.77%, and the coefficient of variation of 5 parallel repeats was less than 20%, showing good accuracy and repeatability. Conclusion The established method has good specificity, high sensitivity and accurate result, which provides a reference for rapid quantitative detection of Staphylococcus aureus.