Zhao Qiang, Li Xing-Fang, Shao Yuanhua, Le X Chris
Division of Analytical and Environmental Toxicology, Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, AB, Canada T6G 2G3.
Anal Chem. 2008 Oct 1;80(19):7586-93. doi: 10.1021/ac801206s. Epub 2008 Aug 30.
Affinity chromatographic assays for thrombin were developed using two aptamers as affinity ligands. The efficient capture and step elution of thrombin with NaClO4 enabled the determination of thrombin by using either absorbance or fluorescence detection. Preconcentration of thrombin on the affinity column improved the detection limit of thrombin to 0.1 nM. Using an aptamer for the fibrinogen-binding site of thrombin and a second aptamer for the heparin-binding site, a sandwich chromatographic assay was developed, showing improved selectivity of thrombin detection and eliminating the need for labeling thrombin in the sample. The increased local concentration of aptamers immobilized on monolithic columns favored the formation of aptamer-thrombin complexes, resulting in improved retention and detection of thrombin at trace levels.
利用两种适体作为亲和配体开发了用于凝血酶的亲和色谱分析方法。用高氯酸钠对凝血酶进行有效捕获和分步洗脱，使得能够通过吸光度或荧光检测来测定凝血酶。凝血酶在亲和柱上的预浓缩将凝血酶的检测限提高到了0.1 nM。利用针对凝血酶纤维蛋白原结合位点的一种适体和针对肝素结合位点的另一种适体，开发了一种夹心色谱分析方法，该方法提高了凝血酶检测的选择性，并且无需对样品中的凝血酶进行标记。固定在整体柱上的适体局部浓度增加有利于适体-凝血酶复合物的形成，从而提高了痕量水平凝血酶的保留率和检测效果。
