Adhesion and survival of electrogenic cells on gold nanopillar array electrodes

Cell-electrode interfaces play a critical role in extracellular recording. Enlarging the electrode surface area with nanostructures yields higher signal-to-noise-ratios due to lower interface impedance. Adhesion and viability of various cell types on large-scale gold nanopillar electrodes to improve cell-electrode coupling were investigated. Cardiac muscle and human embryonic kidney cells survived and adhered well on gold nanopillars. The muscle cells even protruded into inter-pillar cavities with diameters below 100 nm. However, an unexpectedly low viability and adhesion of primary rat neurons was observed on nanopillars. A cross-sectional analysis of the cell-nanopillar interface showed large distances between neuronal cell bodies and nanopillars, whereas the neurites adhered tightly. Furthermore, actin assembly within the neuronal growth cones was modified on nanopillars. In summary, the adhesion response of the investigated cell lines will be beneficial for improved extracellular signalling, whereas a better understanding of neuronal responses to nanotopographies is required to enhance the neuronal viability.