AbstractThe authors describe the identification of an effective binding region of aptamers against glycated (HbA1c) and total haemoglobin (tHb) by using a fluorometric assay. Truncation of the originally selected aptamers from 60 to 46 and 34 nucleotides for HbA1c and tHb, respectively, enhances the affinity for their targets. Moreover, shortening the aptamer sequences leads to a better conformational change after target binding which enabled the integration of the aptamers in a graphene oxide (GO)-based fluorometric assay. First, fluorescein-labelled truncated aptamers were physically absorbed onto the surface of GO surface via π−stacking interaction. This leads to quenching of fluorescence. Once the truncated aptamers bind the target protein, a conformational change is induced which results (a) )in the release of the aptamers from the surface of GO and (b) in the restoration of green fluorescence that is measured at 515 nm. The assay can be carried out in a microtiter plate format in homogeneous solution, this avoiding the steps of immobilization, incubation, and washing that are often necessary in immunoassays. This also reduces the time and the costs of the overall assay and allows for high throughput screening for diabetes. HbA1c can be detected in the range from 5.4 to 10.6%. The assay is selective for HbA1c over other proteins that commonly exist in blood. The results obtained by using this method compare well with those of a turbidimetric immunoassay that is typically applied in clinical laboratories. Graphical abstractTruncated aptamers for total and glycated hemoglobin were selected and integrated into a graphene oxide-based fluorescence detection assay for high-throughput screening for diabetes

中文翻译：

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用于总血红蛋白和糖化血红蛋白的截短适体，以及将它们整合到基于氧化石墨烯的荧光法中，用于糖尿病的高通量筛查

摘要作者描述了使用荧光测定法鉴定针对糖化 (HbA1c) 和总血红蛋白 (tHb) 的适体的有效结合区。将 HbA1c 和 tHb 的最初选择的适体分别从 60 到 46 和 34 个核苷酸截断，增强了对其靶标的亲和力。此外，缩短适体序列会导致目标结合后更好的构象变化，这使得适体能够整合到基于氧化石墨烯 (GO) 的荧光测定中。首先，荧光素标记的截短适体通过 π-堆积相互作用物理吸附到 GO 表面。这导致荧光猝灭。一旦截短的适体与目标蛋白结合，诱导了构象变化，导致（a））适体从 GO 表面释放，（b）恢复在 515 nm 处测量的绿色荧光。该测定可以在均质溶液中以微量滴定板形式进行，这避免了免疫测定中通常需要的固定、孵育和洗涤步骤。这也减少了整个检测的时间和成本，并允许对糖尿病进行高通量筛选。HbA1c 的检测范围为 5.4% 至 10.6%。与血液中常见的其他蛋白质相比，该测定对 HbA1c 具有选择性。使用这种方法获得的结果与通常用于临床实验室的比浊免疫测定法的结果相当。