Fully printed and flexible multi-material electrochemical aptasensor platform enabled by selective graphene biofunctionalization

The demand for flexible biochemical sensors has increased with advances in computational functionality and wireless communication. Advances in materials science and biochemistry have enabled the development and fabrication of biosensors for selective detection of biological analytes leveraging ink-printed technologies, including in flexible form-factors. However, despite these advances, minimal effort has been devoted to translating the multi-material, three-electrode electrochemical cell, which is widely regarded as the standard for laboratory-scale studies, into a flexible form-factor for use in immunosensors, especially in a manner that is compatible with rapid and scalable additive manufacturing. Here, we report a fully printed and flexible electrochemical non-enzymatic immunosensor platform that integrates four chemically compatible inks and a non-covalent, two-step biofunctionalization scheme. The robustness of the platform is demonstrated using a model aptasensor that enables lysozyme detection using both electrochemical impedance spectroscopy and square wave voltammetry. The flexible, fully ink-printed aptasensor shows competitive performance to commercially available rod/disc electrodes in a bath cell. Overall, this work establishes a methodology for high-throughput fabrication of robust, flexible, multi-material, three-electrode immunosensors that can be generalized to a range of biosensor applications.

随着计算功能与无线通信技术的进步，对柔性生化传感器（biochemical sensors）的需求日益增长。材料科学与生物化学领域的突破，推动了生物传感器的研发与制备——这类传感器可借助油墨印刷技术（包括柔性形态）实现对生物分析物的选择性检测。然而，尽管取得了这些进展，将实验室规模研究中被广泛视为标准的多材料三电极电化学池（three-electrode electrochemical cell）转化为适用于免疫传感器的柔性形态（尤其是以兼容快速、可扩展增材制造的方式）的努力却寥寥无几。在此，我们报道了一种全印刷柔性电化学非酶免疫传感器平台，该平台集成了四种化学兼容的油墨与非共价两步生物功能化方案。通过电化学阻抗谱（electrochemical impedance spectroscopy）和方波伏安法（square wave voltammetry）对溶菌酶检测的模型适体传感器进行测试，验证了该平台的稳健性。这种柔性全油墨印刷适体传感器在浴槽电池中表现出可与商用棒状/圆盘电极相媲美的性能。总体而言，本研究建立了一套高通量制备稳健、柔性、多材料三电极免疫传感器的方法，该方法可推广至多种生物传感器应用场景。