基于纳米抗体和石墨烯/金复合材料的免疫传感器检测日本血吸虫循环抗原的研究

IMPEDIMETRIC IMMUNOSENSOR BASED ON NANOBODY AND GOLD NANOPARTICLES MODIFIED GRAPHENE PAPER FOR DETECTION OF SCHISTOSOMA JAPONICUM CIRCULATING ANTIGEN

将抗日本血吸虫SEA纳米抗体固定于镀金的石墨烯薄膜上,制备一种新型的阻抗型免疫传感器检测日本血吸虫循环抗原。使用扫描电镜、原子力显微镜和拉曼光谱对石墨烯薄膜及石墨烯/金复合材料进行了表征,并对制备的免疫传感器的特异性和灵敏度进行了测试。结果显示,所制备的免疫传感器具有较好的特异性和灵敏度,与曼氏裂头蚴、刚地弓形虫、颚口线虫、简单异尖线虫、华支睾吸虫和卫氏并殖吸虫抗原没有交叉反应,检测日本血吸虫可溶性虫卵抗原达到0.01 ng/m L水平;血吸虫病患者血清的阳性检出率为66.7%,优于现有试剂盒ELISA法56.7%的检出率,与ELISA的符合率为90%。该免疫传感器检测日本血吸虫循环抗原具有较高的灵敏度和特异性,制作方法简便、快速等优点,具有较好的应用潜能。

In this study,a new type of impedimetric immunosensor was constructed based on graphene paper for detection of Schistosoma japonicum circulating antigen.The prepared graphene paper was modified with nanobody and gold nanoparticls and the surface morphology and crystal structure of the graphene paper was characterized by scanning electron microscope,atomic force microscope,raman spectroscopy.At the same time,specificity and sensibility of this immuosensor were analyzed.It is demonstrated that the developed impedimetric immunosensor possesses excellent specificity and sensibility,the detection level of S.japonicum soluble egg antigen（SEA） reaches 0.01 ng/mL;The detection rate of suspected schistosomiasis patients was 66.7%,which was better than that （56.7%） of ELISA,and the coincidence rate with ELISA was 90%.The immunosensor has high sensitivity and specificity for detecting S.japonicum circulating antigen.The method is simple,fast and has good potential for application.