便携式电流型葡萄糖传感器快速检测致奶牛乳腺炎金黄色葡萄球菌的研究

The exploration of rapid detection of Staphylococus aureus from bovine mastitis based on the Portable Amperometric Glucose Sensor

为探索基于便携式电流型葡萄糖传感器对致奶牛乳腺炎金黄色葡萄球菌(S.aureus)的快速检测新技术的可行性,本研究选择和制备了适用于该检测系统,并具有对目标菌严格选择性的培养基,优化培养物中葡萄糖(Glc)初始浓度、培养检测时间、p H值和温度等参数,依据培养前后培养物中Glc含量差值的变化直接对新鲜牛乳样品中的目标菌进行定性和定量检测分析。结果显示,对6 h培养物进行检测时,即可获得Glc消耗量与培养物中S.aureus浓度的对应线性关系,实现对菌液浓度为103cfu/m L^107cfu/m L培养物的初步快速检测,最低检出限为2.6×102cfu/m L;对不能获得判别结果的培养物需要继续培养至24 h时再测定,即可实现对菌液浓度为101cfu/m L^102cfu/m L培养物的检测;对照国标方法确定标准曲线并进行验证试验;特异性和抗干扰试验表明该方法具有良好的特异性和抗其他细菌污染干扰的特性。本研究建立的方法可以直接检测牛的新鲜乳样,具有简便、经济、快速及灵敏等方面具有显著优势,为我国中、小型奶牛场和基层兽医站提供了一种初步快速检测致奶牛乳腺炎S.aureus的方法。

To explore a novel method for rapid detection of Staphylococcus aureus from the diseased cows based on the Portable Amperometric Glucose Sensor （Personal glucose meter, PGM）. The suitable and selective medium was selected and prepared, and experiment parameters such as initial concentration of glucose in the medium, detection time, incubation temperature and pH were optimized for the detection of S.aureus in milk samples, the results showed the bacteria can be quantificational detected based on glucose consumption in culture system using the PGM. In this study, under the optimized conditions （37± 1℃ and pH7.4）, measurement results can be obtained within 6 hours, which exhibited a linear relationship between glucose concentration and S.aureus concentration, in the range of 103 to 107 cfu/mL with a low detection limit of 2.6×10^2 cfu/mL, and the testing process of 101 to 102 cfu/mL can be completed within 24 hours. The detection results of S.aureus remained unaffected in the presence of other bacteria in another analysis. In addition, the proposed method is a low-cost, rapid and accurate analytical tool in detection of S.aureus for treating bovine mastitis.