基于氧化石墨烯生物免疫传感器检测副溶血弧菌的研究

副溶血弧菌(Vibrio parahaemolyticus)是最为严重的水产动物致病菌之一,准确即时的检测手段是预防控制该菌传播的关键所在.通过量子点(QDs)标记副溶血弧菌鞭毛蛋白抗体(Ab),利用生物免疫传感器技术实现副溶血弧菌的快速、特异性检测.结果显示,QDs-Ab的荧光通过加入氧化石墨烯(G0)产生淬灭,构建了捕获目标细菌的探针,氧化石墨烯最适淬灭浓度为60 ng/ml.细菌捕获探针中加入副溶血弧菌后,能够检测到重新恢复强度的绿色荧光.副溶血弧菌的检出限达到104 CFU/mL.针对副溶血弧菌设计的生物免疫传感器的特异性,选取灿烂弧菌、溶藻胶弧菌、迟缓爱德华氏菌和嗜水气单胞菌作为对照,结果显示,对照组不能明显引起荧光强度的改变,而试验组却能显著提高荧光强度.该研究建立的基于荧光能量共振转移(FRET)的具有高灵敏度和特异性的生物传感器检测方法在细菌的早期诊断中有良好的应用潜质.

A Graphene Oxide-based Immuno-biosensor for Vibrio parahaemolyticus Detection

Vibrio parahaemolyticus is the leading causal agent of human acute gastroenteritis.Real-time accurate detection means is the key to prevention and control of its spread.This study provided a novel detection strategy for realizing rapid and specific determination of V.parahaemolyticus by labeling its monoclonal antibody (Ab) with quantum dots (QDs).The results showed that the fluorescence of these QDs-Ab bioconjugates was quenched by graphene oxide (GO) to produce a bacterium capture probe,And the optimal quenched concentration of GO was 60 ng/ml.When the bacterium capture probe was exposed to the target,green color fluorescence was tumed on by releasing the QDs-Ab due to the antibody antigen combination.The detection limit of V.parahaemolyticus was 104 CFU/ml based on 3 times signal-to-noise ratio.The specificity of the FRET sensor towards V.parahaemolyticus was examined by comparing with controls such as V.splendidus,V.alginolyticus,Edwardsiella tarda and Aeromonas hydrophila with the same condition.The controls couldn't cause obvious fluorescence alteration,while the target resulted in significant fluorescence enhancement.This strategy could be further used as a universal method for any bacterial determination by changing the conjugated antibodies in early disease diagnosis.Therefore,the sensor has good potential to expand its application to the early diagnosis and determination of bacteria.