Tianjin Key Laboratory of Molecular Optoelectronic Sciences, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China.
Institute for Advanced Interdisciplinary Research, University of Jinan, Jinan 250011, P. R. China.
Anal Chem. 2021 Nov 16;93(45):15167-15174. doi: 10.1021/acs.analchem.1c03683. Epub 2021 Nov 1.
Achieving biosensors of high sensitivity and reliability is extremely significant for early diagnosis and treatment of tumor diseases. Herein, a novel organic field-effect transistor (OFET)-based biosensor was developed and applied for carcinoembryonic antigen (CEA) bioassay. This OFET-based biosensor can respond sensitively to the antigen-antibody immune-recognition reaction under illumination and darkness, respectively, thereby generating electrical signal changes of source-drain current () and threshold voltage (). The OFET-based biosensor exhibits detection limits for CEA detection of 0.5 and 0.2 pM, respectively, using and as the response signals under darkness. When a specific intensity of light is applied, light will influence the charge-carrier transport process in the conductive channel, thus causing biosignals to turn into higher electrical signal changes of photocurrent and threshold voltage under illumination. Compared with the detection results in the dark, the biosensor exhibits higher sensitivity for CEA detection under illumination with detection limits of 13.5 and 16.9 fM. Also, multisignal outputs effectively improve the reliability of the biosensor for CEA detection. Consequently, with powerful detection functions, this OFET-based biosensor is expected to become a high-performance biosensing platform for the detection of various biological substances in the future.
实现高灵敏度和可靠性的生物传感器对于肿瘤疾病的早期诊断和治疗具有重要意义。在此，我们开发了一种新型基于有机场效应晶体管 (OFET) 的生物传感器，并将其应用于癌胚抗原 (CEA) 的生物测定。该基于 OFET 的生物传感器可以分别在光照和黑暗下对抗原-抗体免疫识别反应做出灵敏响应，从而产生源漏电流 (ID) 和阈值电压 (VT) 的电信号变化。基于 OFET 的生物传感器在黑暗条件下使用 ID 和 VT 作为响应信号，对 CEA 的检测限分别为 0.5 和 0.2 pM。当施加特定强度的光时，光会影响导电沟道中的电荷载流子输运过程，从而导致生物信号在光照下转变为更高的光电流和阈值电压的电信号变化。与黑暗条件下的检测结果相比，该生物传感器在光照下对 CEA 的检测具有更高的灵敏度，检测限分别为 13.5 和 16.9 fM。此外，多信号输出可有效提高生物传感器对 CEA 检测的可靠性。因此，该基于 OFET 的生物传感器具有强大的检测功能，有望成为未来用于检测各种生物物质的高性能生物传感平台。
