【摘要】 利用GQDs/Pr³⁺纳米探针的荧光从关到开的光致发光变化,建立了检测凝血酶活性的新方法。稀土离子Pr³⁺与GQDs表面的羧酸基团结合而组装到GQDs表面形成GQDs/Pr³⁺复合物,导致GQDs荧光猝灭,当加入凝血酶后,GQDs/Pr³⁺复合物解体,使得GQDs荧光恢复,该荧光强度与凝血酶活性呈正比,据此实现了凝血酶的检测,线性范围为0.1²5nmol·L^-1,检测限为0.06nmol·L^-1。本方法不需要对GQDs的表面进行任何功能化修饰,也不需要使用凝血酶适配体,利用GQDs荧光开关转变即可实现微量凝血酶的检测。更多还原

【Abstract】 Graphene quantum dots（GQDs）,one of the graphene nanosheets with size less than 100 nm,are often used for biological and chemical sensing due to their excellent optical and electronic properties.Here,we report an approach for detection of thrombin based on the photoluminescence change of GQDs/Pr³⁺probes from off to on state.The mechanism of the sensing system has been investigated.Rare earth ions Pr³⁺could assemble onto the surface of GQDs and cause the fluorescence quenching of GQDs because Pr³⁺ions can coordinate to the carboxylate groups on the surface of GQDs,after the introduction of thrombin,thrombin can coordinate to Pr³⁺and thus release GQDs from GQDs/Pr³⁺,resulting in the fluorescence restoration of GQDs.This nanosensor needs no further surface functionalization of GQDs or employment of thrombin aptamers.This sensor can be used to detect thrombin in the range of 0.1²5nmol·L^-1 with a detection limit as low as 0.06nmol·L^-1.更多还原