School of Mechanical Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250353, China.
Shandong Institute of Mechanical Design and Research, Jinan 250353, China.
Nanoscale. 2024 Nov 21;16(45):20864-20884. doi: 10.1039/d4nr03481c.
Field-effect transistor (FET)-based biosensors not only enable label-free detection by measuring the intrinsic charges of biomolecules, but also offer advantages such as high sensitivity, rapid response, and ease of integration. This enables them to play a significant role in disease diagnosis, point-of-care detection, and drug screening, among other applications. However, when FET sensors detect biomolecules in physiological solutions (such as whole blood, serum, ), the charged molecules will be surrounded by oppositely charged ions in the solution. This causes the effective charge carried by the biomolecules to be shielded, thereby significantly weakening their ability to induce charge rearrangement at the sensing interface. Such shielding hinders the change of carriers inside the sensing material, reduces the variation of current between the source and drain electrodes of the FET, and seriously limits the sensitivity and reliability of the device. In this article, we summarize the research progress in overcoming the Debye screening effect in FET-based biosensors over the past decade. Here, we first elucidate the working principles of FET sensors for detecting biomarkers and the mechanism of the Debye screening. Subsequently, we emphasize optimization strategies to overcome the Debye screening effect. Finally, we summarize and provide an outlook on the research on FET biosensors in overcoming the Debye screening effect, hoping to help the development of FET electronic devices with high sensitivity, specificity, and stability. This work is expected to provide new ideas for next-generation biosensing technology.
场效应晶体管（FET）生物传感器不仅通过测量生物分子的固有电荷实现无标记检测，还具有高灵敏度、快速响应和易于集成等优点。这使得它们在疾病诊断、即时检测和药物筛选等应用中发挥着重要作用。然而，当 FET 传感器在生理溶液（如全血、血清等）中检测生物分子时，带电荷的分子会被溶液中带相反电荷的离子包围。这导致生物分子所携带的有效电荷被屏蔽，从而大大削弱了它们在传感界面诱导电荷重排的能力。这种屏蔽会阻碍传感材料内部载流子的变化，减少 FET 的源极和漏极之间电流的变化，严重限制了器件的灵敏度和可靠性。在本文中，我们总结了过去十年中克服 FET 生物传感器中 Debye 屏蔽效应的研究进展。首先，我们阐明了用于检测生物标志物的 FET 传感器的工作原理和 Debye 屏蔽的机制。随后，我们强调了克服 Debye 屏蔽效应的优化策略。最后，我们总结并展望了克服 Debye 屏蔽效应的 FET 生物传感器的研究，希望为高灵敏度、特异性和稳定性的 FET 电子器件的发展提供新的思路。这项工作有望为下一代生物传感技术提供新的思路。
