Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
Department of Chemical Engineering, and Wilton E. Scott Institute for Energy Innovation, Carnegie Mellon University, Pittsburgh, PA, 15213, USA.
Nat Commun. 2021 Dec 6;12(1):7077. doi: 10.1038/s41467-021-27361-x.
Sensing of clinically relevant biomolecules such as neurotransmitters at low concentrations can enable an early detection and treatment of a range of diseases. Several nanostructures are being explored by researchers to detect biomolecules at sensitivities beyond the picomolar range. It is recognized, however, that nanostructuring of surfaces alone is not sufficient to enhance sensor sensitivities down to the femtomolar level. In this paper, we break this barrier/limit by introducing a sensing platform that uses a multi-length-scale electrode architecture consisting of 3D printed silver micropillars decorated with graphene nanoflakes and use it to demonstrate the detection of dopamine at a limit-of-detection of 500 attomoles. The graphene provides a high surface area at nanoscale, while micropillar array accelerates the interaction of diffusing analyte molecules with the electrode at low concentrations. The hierarchical electrode architecture introduced in this work opens the possibility of detecting biomolecules at ultralow concentrations.
对临床相关生物分子（如低浓度神经递质）的检测能够实现多种疾病的早期发现和治疗。研究人员正在探索多种纳米结构，以期实现对生物分子的检测，其灵敏度超过皮摩尔范围。然而，人们已经认识到，仅仅对表面进行纳米结构化还不足以将传感器灵敏度提高到飞摩尔水平。在本文中，我们通过引入一个传感平台来打破这一障碍/限制，该平台使用由 3D 打印的银微柱构成的多长度尺度电极结构，这些微柱上装饰有石墨烯纳米薄片，并利用该平台演示了对多巴胺的检测，其检测限低至 500 飞摩尔。石墨烯在纳米尺度上提供了大的表面积，而微柱阵列则加速了低浓度下扩散分析物分子与电极的相互作用。本工作中引入的分层电极结构为检测超低浓度的生物分子开辟了可能性。
