액체금속을 활용한 플렉서블 섬유상 전극 제조 및 도파민 센서로의 응용

Abstract

Gallium-based liquid metals have gained significant attention as promisingmaterial platforms for flexible bioelectronics owing to their fluidic behavior but still metallic. However, low electrochemical stability owing to oxidation may limit the use of bioelectronicsthat typically operate under physiological conditions. Here, we developed a liquidmetal core/polymer shell fiber platform for flexibility. Then, nanostructured conductivepoly(3,4-ethylenedioxythiophene) (PEDOT) was encapsulated on the liquid metal surfaceto prevent oxidation. Mechanical property measurement demonstrated that the platformdisplayed high flexibility and low Young’s modulus that could minimize the mechanicalmismatch between the fiber platform and soft human tissues. PEDOT encapsulation on theliquid metal surface offered the fiber platform-based electrode considerably higher electrochemicalproperties, such as lower impedance and higher charge storage capacity. Theimproved electrochemical performance enables the liquid metal-based fiber electrode tobe used for electrochemical dopamine (DA) monitoring. This study demonstrated that thePEDOT structured flexible electrode had a sensitivity of 0.218±0.022 μA/μM and a limit ofdetection of 150 nM. Finally, the electrode could effectively detect DA under a plethora ofbyproducts produced by human metabolism. All the results confirmed the flexibility andremarkable electrochemical properties of the prepared liquid metal-based electrode,opening numerous design opportunities for next-generation liquid metal-based bioelectronics.