Sun Dapeng, Xie Jing, Chen Ching-Jung, Liu Jen-Tsai
Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China; Research Center for Materials Science and Opti-Electronic Technology, College of Materials Science and Opti-Electronic Technology, University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China.
Institute of Microelectronics of Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, No.19 A Yuquan Road, Beijing 100049, China.
Colloids Surf B Biointerfaces. 2022 Jun;214:112445. doi: 10.1016/j.colsurfb.2022.112445. Epub 2022 Mar 5.
Glycated albumin(GA), a biomarker which has great potential to replace glycated hemoglobin in the diagnosis and treatment of diabetes, is being extensively studied by scientists, especially in preventive medicine. Aptamers, as novel probes, have attracted much attention due to their high specificity, wide storage conditions, and simple preparation. However, the interaction mechanism between GA and its aptamer is still unclear, hindering the progress of diabetic aptamer sensors into clinical testing. In this study, the interaction mechanism between GA and its aptamer was evaluated for the first time using surface plasmon resonance by changing the pH value, salt concentration and temperature. The successful preparation of the sensor chip is proved by the water contact angle, Atomic Force Microscope, and the X-ray photoelectron spectroscopy. This study shows that the pH can greatly affect the formation of a complex from the interaction between the aptamer and GA. The interaction mechanism between GA aptamer and GA was caused by electrostatic force. Otherwise, this is the first time to detect protein isoelectric point (pI) using SPR. This study provides an important reference for researchers of aptamer sensors from the perspective of detection environment, and promotes the use of aptamer sensors to the clinic.
糖化白蛋白（GA）作为一种在糖尿病诊断和治疗中极有可能取代糖化血红蛋白的生物标志物，正受到科学家们的广泛研究，尤其是在预防医学领域。适体作为新型探针，因其高特异性、宽泛的储存条件和简单的制备方法而备受关注。然而，GA与其适体之间的相互作用机制仍不明确，这阻碍了糖尿病适体传感器进入临床试验的进程。在本研究中，首次通过改变pH值、盐浓度和温度，利用表面等离子体共振评估了GA与其适体之间的相互作用机制。通过水接触角、原子力显微镜和X射线光电子能谱证明了传感器芯片的成功制备。本研究表明，pH值可极大地影响适体与GA相互作用形成复合物的过程。GA适体与GA之间的相互作用机制是由静电力引起的。此外，这是首次利用表面等离子体共振检测蛋白质等电点（pI）。本研究从检测环境的角度为适体传感器研究人员提供了重要参考，并推动适体传感器在临床上的应用。
