摘要
构建了新型甲胎蛋白(AFP)夹心免疫传感器。采用金纳米粒子-氧化石墨烯-普鲁士蓝纳米立方体(Au NP-GO-PBNCs)纳米复合材料标记甲胎蛋白(AFP)二抗,将制备的金-聚多巴胺-四氧化三铁(Au-PDAFe_3O_4)磁性纳米复合物固定在自制的磁性电极表面,通过吸附作用固定AFP一抗,用牛血清白蛋白(BSA)封闭电极上的非特异性吸附位点。在37℃下与AFP抗原溶液孵育50 min,最后将电极放入Au NP-GO-PBNCs纳米复合材料标记的二抗溶液中孵育,基于此建立了采用普鲁士蓝(PB)标记的的夹心免疫传感器检测AFP的方法。在最佳实验条件下,PB催化H_2O_2氧化的响应电流与AFP的浓度表现出两段线性关系,线性范围分别为0.005~1.000 ng/m L和1~20 ng/m L,检出限(LOD,S/N=3)为1.0 pg/m L。本方法具有灵敏度高、选择性好的特点。
Abstract The Au-PDA-Fe3O4 decorated graphene oxide electrode was modified with Prussion blue-secondary antibodies for determination of cancer biomarker a-letoprotein （AFP） with great sensitivity. Scanning electron microscopy （ SEM） , X-ray diffraction （ XRD） and ultraviolet-visible absorption spectrometry were used to characterize the structure of the material. Greatly enhanced sensitivity for the cancer biomarker is based on a dual signal amplification strategy. First, Fe3O4-PDA.Au used for the biosensor platform increased the surface area to capture a large amount of primary antibodies （ Ab1 ） , which resulted in amplification of the detection response. Second, graphene oxide allowed several binding events of PB-Ab2. Enhanced sensitivity was also achieved by introducing the multibioconjugates of Ab2-PB-GO onto the electrode surface through ＂ sandwich＂ immunoreactions. The test result shows that there are linear relationships between current and AFP concentrations ranging from 0. 005 ng/mL to 1 ng/mL and 1 ng/mL to 20 ng/mL, with the low detection limit （LOD） of 1.0 pg/mL. This immunosensor is simple, low-cost and sensitive and shows a great potential in biomedicine, clinical diagnosis and health examination.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2017年第8期1180-1187,共8页
Chinese Journal of Analytical Chemistry
基金
国家自然科学基金项目(No.21461015)
电分析化学国家重点实验室开放课题(No.SKLEAC201602)
江西省自然科学重点重大项目(No.20161ACB21002)
江西省青年科学家培养计划(No.20153BCB23035)
江西省食品药品监督管理局资助科研项目(No.2016SP04)资助~~
