Abstract
Hydrogel-based flexible microelectrodes have garnered considerable attention recently for soft bioelectronic applications. We constructed silver nanowire (AgNW) micropatterns on various substrates, via a simple, cost-effective, and eco-friendly method without aggressive etching or lift-off processes. Polyethylene glycol (PEG) photolithography was employed to construct AgNW patterns with various shapes and sizes on the glass substrate. Based on a second hydrogel gelation process, AgNW patterns on glass substrate were directly transferred to the synthetic/natural hydrogel substrates. The resultant AgNW micropatterns on the hydrogel exhibited high conductivity (ca. 8.40 × 103 S cm−1) with low sheet resistance (7.51 ± 1.11 Ω/sq), excellent bending durability (increases in resistance of only ~3 and ~13% after 40 and 160 bending cycles, respectively), and good stability in wet conditions (an increase in resistance of only ~6% after 4 h). Considering both biocompatibility of hydrogel and high conductivity of AgNWs, we anticipate that the AgNW micropatterned hydrogels described here will be particularly valuable as highly efficient and mechanically stable microelectrodes for the development of next-generation bioelectronic devices, especially for implantable biomedical devices.
Highlights
The Polyethylene glycol (PEG) precursor solution was dropped onto the AgNW-coated glass, and a silane-treated cover glass was placed over the PEG precursor solution
Upon confirming the successful fabrication of AgNW patterns on both the glass and hydrogel substrates, we investigated the electrical properties of AgNW micropatterns as a function of spin-coating speeds and AgNW concentrations; these variables can determine the AgNW network density
These results show that this method enables to apply into various bioelectronics applications using various gel species with different intrinsic properties
Summary
Youngsang Ko1, Jeonghun Kim 2, Dabum Kim1,YusukeYamauchi[2], Jung Ho Kim2 & Jungmok You[1]. To utilize the CuNWs as an electrode material, further uses of an inert-gas or vacuum environment are required[41,42,43,44] From these backgrounds, till solution-processable AgNWs under ambient condition can be considered as a proper candidate in conductive materials for the development of high-performance bioelectronic devices, especially, exposing to wet environments. The photolithographic method is a time-consuming process that requires aggressive etching with toxic chemicals that can damage the electrical and mechanical properties of the AgNWs. More recently, our group demonstrated that a conductive polymer, organic conductor, i.e., poly(3,4-ethylenedioxythiophene) (PEDOT), can be successfully patterned on hydrogel substrates via only solution-based processes comprising solution phase monomer casting and oxidative polymerization and PEG photolithography[45]. Our investigation revealed that these silver nanowire-based microelectrodes on hydrogels exhibited good electrical properties, excellent bending durability, and long-term stability in wet conditions
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
