ACS applied materials & interfaces | 2019
MEA Recordings and Cell-Substrate Investigations with Plasmonic and Transparent, Tunable Holey Gold.
Abstract
Micro-electrode arrays are widely used in such different fields such as neurobiology or biomedicine to read out electrical signals from cells or biomolecules. One way to improve micro-electrode applications is the development of novel electrode materials with enhanced or additional functionality. In this study, we fabricated macro-electrodes and micro-electrode arrays containing gold penetrated by nanohole arrays as a conductive layer. We used this holey gold to optically excite surface plasmon polaritons which lead to a strong increase in transparency, an effect that is further enhanced by the plasmon s interaction with cell culture medium. Further, we demonstrate that the novel transparent micro-electrode arrays are as suitable for recording cellular electrical activity as standard devices. Moreover, we prove using spectral measurements and finite difference time domain simulations that plasmonically induced transmission peaks of holey gold redshift upon sensing medium or cells in close vicinity (<30 nm) to the substrate. Thus, we establish plasmonic and transparent holey gold as a material suitable for cellular electrical recordings and biosensing applications.