The College of Materials Science and Engineering, Shanghai University, Shanghai, 200072, People's Republic of China.
Key Laboratory of Multifunctional Nanomaterials and Smart Systems, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215125, People's Republic of China.
Analyst. 2024 Jan 29;149(3):958-967. doi: 10.1039/d3an02115g.
Cortisol hormone imbalances can be detected through non-invasive sweat monitoring using field-effect transistor (FET) biosensors, which provide rapid and sensitive detection. However, challenges like skin compatibility and integration with sweat collection have hindered FET biosensors as wearable sensing platforms. In this study, we present an integrated wearable sticker for real-time cortisol detection based on an extended-gate AlGaN/GaN high electron mobility transistor (HEMT) combined with a soft bottom substrate and flexible channel for sweat collection. The developed devices exhibit excellent linearity ( = 0.990) and a high sensitivity of 1.245 μA dec for cortisol sensing from 1 nM to 100 μM in high-ionic-strength solution, with successful cortisol detection demonstrated using authentic human sweat samples. Additionally, the chip's microminiature design effectively reduces bending impact during the wearable process of traditional soft binding sweat sensors. The extendedgate structure design of the HEMT chip enhances both width-to-length ratio and active sensing area, resulting in an exceptionally low detection limit of 100 fM. Futhermore, due to GaN material's inherent stability, this device exhibits long-term stability with sustained performance within a certain attenuation range even after 60 days. These stickers possess small, lightweight, and portable features that enable real-time cortisol detection within 5 minutes through direct sweat collection. The application of this technology holds great potential in the field of personal health management, facilitating users to conveniently monitor their mental and physical conditions.
皮质醇激素失衡可以通过使用场效应晶体管 (FET) 生物传感器进行非侵入性汗液监测来检测，该传感器提供快速和敏感的检测。然而，像皮肤兼容性和与汗液收集的集成等挑战一直阻碍着 FET 生物传感器作为可穿戴感测平台的发展。在这项研究中，我们提出了一种基于扩展栅 AlGaN/GaN 高电子迁移率晶体管 (HEMT) 的集成可穿戴贴纸，该晶体管与软底衬底和用于汗液收集的柔性通道相结合，用于实时皮质醇检测。所开发的器件在高离子强度溶液中对 1 nM 至 100 μM 的皮质醇表现出出色的线性度（= 0.990）和 1.245 μA dec 的高灵敏度，成功地使用真实的人体汗液样本进行了皮质醇检测。此外，该芯片的微型设计有效地减少了传统软贴合汗液传感器在可穿戴过程中的弯曲影响。HEMT 芯片的扩展栅结构设计提高了宽长比和有源感测面积，从而实现了 100 fM 的超低检测限。此外，由于 GaN 材料的固有稳定性，即使在 60 天后，该器件仍在一定衰减范围内保持性能持续，表现出长期稳定性。这些贴纸具有体积小、重量轻和便携的特点，通过直接汗液收集可在 5 分钟内实现实时皮质醇检测。该技术在个人健康管理领域具有很大的应用潜力，使用户能够方便地监测自己的身心状况。
