Chen Chaohui, Song Qingyuan, Lu Wangting, Zhang Zhengtao, Yu Yanhua, Liu Xiaoyun, He Rongxiang
Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education, College of Photoelectric Materials and Technology, Jianghan University Wuhan 430056 PR China
RSC Adv. 2021 Nov 24;11(60):37917-37922. doi: 10.1039/d1ra07375c. eCollection 2021 Nov 23.
Highly sensitive detection of DNA is of great importance for the detection of genetic damage and errors for the diagnosis of many diseases. Traditional highly sensitive organic electrochemical transistor (OECT)-based methods mainly rely on good conductivity materials, which may be limited by complex synthesis and modification steps. In this work, DNA biosensor based on OECT and hybridization chain reaction (HCR) signal amplification was demonstrated for the first time. Au nanoparticles were electrochemically deposited on the Au gate electrode to increase the surface area. Then, the HCR products, long negatively charged double-stranded DNA, were connected to the target by hybridization, which can increase the effective gate voltage offset of OECT. This sensor exhibited high sensitivity and even 0.1 pM target DNA could be directly detected with a significant voltage shift. In addition, it could discriminate target DNA from the mismatched DNA with good selectivity. This proposed method based on HCR in DNA detection exhibited an efficient amplification performance on OECT, which provided new opportunities for highly sensitive and selective detection of DNA.
DNA的高灵敏度检测对于检测遗传损伤和错误以诊断多种疾病至关重要。传统的基于高灵敏度有机电化学晶体管（OECT）的方法主要依赖于良好的导电材料，这可能受到复杂合成和修饰步骤的限制。在这项工作中，首次展示了基于OECT和杂交链式反应（HCR）信号放大的DNA生物传感器。通过电化学沉积将金纳米颗粒沉积在金栅电极上以增加表面积。然后，HCR产物，即带负电荷的长双链DNA，通过杂交与靶标连接，这可以增加OECT的有效栅极电压偏移。该传感器表现出高灵敏度，甚至可以直接检测到0.1 pM的靶标DNA，且有明显的电压偏移。此外，它能够以良好的选择性区分靶标DNA和错配DNA。这种基于HCR的DNA检测方法在OECT上表现出高效的放大性能，为DNA的高灵敏度和选择性检测提供了新的机会。
