中文摘要：

利用凝血酶的两条核酸适配体与凝血酶的高亲和力构建了三明治结构，利用磁性纳米颗粒的磁性分离技术，设计并制作了一种新型的荧光纳米生物传感器，用其检测凝血酶．此法对凝血酶的响应线性范围为2．24×10^-11～4．03×10^-9mol／L，其线性方程为I=0．9758×10^11c-2．628，检出限为1．0×10^-11mol／L，对浓度为2．68×10^-10mol／L的凝血酶检测10次，其RSD为2．56％，测得的荧光信号稳定，24h后测定并无衰减，具有很高的检测特异性和灵敏度．

英文摘要：

Thrombin is an important enzyme in physiology. It palys an important role in some physiological and pathological process, such as blood solidification, wound cicatrization and inflammation. Therefore, thrombin detection is very important in medicine. A novel nano-biosensor based on aptamer was designed and thrombin detection with sandwich-type based on magnetic separation was proposed. The equation of calibration plot is 1 =0. 9758×10^11c -6. 68 in the concentration range of 2. 24×10^-11-4.03×10^-9 mol/L and the detective limit is 1×10^-11mol/L of thrombin. The relative standard deviation（n=10） was 2.56%. The fluorescence intensity obtained was very stable, even no attenuation observed after 24 h. The experiments results demonstrate that the proposed method possesses the feasibility, high specificity and sensitivity. It is also hopeful to be applied to the field of biomedicine.