This title appears in the Scientific Report : 2014 

Voltage-controlled stimulation of HL-1 cells with nanocavity arrays
Czeschik, Anna (Corresponding author)
Rinklin, Philipp / Offenhäusser, Andreas / Wolfrum, Bernhard
Bioelektronik; PGI-8
NanoBioTech Montreux, Montreux (Switzerland), 2013-11-18 - 2013-11-20
Helmholtz Young Investigators Group
Sensorics and bioinspired systems
Multielectrode arrays (MEA) have been widely used for the analysis of intercellular communication in cellular networks and pharmacological studies. Generally they are used for the recording of action potentials but have also been applied in the detection of neurotransmitter release. They allow for non-invasive multi-channel measurements and high-throughput screening. Crucial parameters for the performance of on-chip electrical stimulation and recording are the electrode impedance, sealingresistance between the cell and the electrode, and electrode size and density. These factors determine the noise level, leakage currents, necessary stimulation voltages/currents, and the spatial resolution of the system. The improvement of the electrode-cell interface has gathered great attention in the last years. Nanocavity arrays provide large electrode areas combined with a small aperture to access the reservoir above the electrode and therefore allow for low impedance and highly localized measurements. MEA-based extracellular action potential recordings and electrical stimulation of electrogenic cells are well established. Based on a formerly published method, we now present a simplified fabrication protocol for designing nanocavity arrays, which is independent of CMOS technology. This method allows for flexible and easy modification of standard MEAs to improve their electrode characteristics. We combine the advantages in electrode impedance and spatial resolution of these devices with voltage-controlled stimulation of a cardiomyocyte-like cell line (HL-1). We induce propagating action potential waves, to show the possibility of pacing cardiac tissue with the nanocavity arrays. The high-jacking of the network’s pacemaker and the influence on action potential propagation and frequency by stimulation are demonstrated and illustrated using a cross-correlation analysis of calcium imaging sequences.