Measurement of sealing resistance of cell-electrode interfaces in neuronal cultures using impedance spectroscopy

Abstract

Sealing resistance is highly significant with respect to the electrical neuron-electrode contact because it decreases the stimulation threshold of neurons cultured on a planar micro-electrode array. A method is proposed for measurement of the sealing resistance using impedance spectroscopy. The effect of the sealing resistance on the total impedance spectrum of a cell-electrode interface is modelled for complete coverage of the electrode by the cell. Sensitivity analysis demonstrates that the impedance spectrum is determined by four parameters: two electrode parameters, the sealing resistance and the shunt capacitance between the lead of the electrode and the culture medium. Experimental verification of the model is performed by simultaneous measurement of the impedance spectrum and electrode coverage. A good and unique fit between the simulated and measured impedance spectra was obtained by varying the two electrode parameters and the sealing resistance.

Effective parameters for stimulation of dissociated cultures using multi-electrode arrays

“…Knowing a set of stimuli that are reliably and consistently effective is essential for long-term experiments on the development of functional networks, as well as for research on learning in-vitro Shahaf and Marom, 2001). While the electrical properties of MEA electrodes have been described in the literature (Kovacs, 1994;McAdams et al, 1995;Buitenweg et al, 1998;McIntyre and Grill, 2001), the published knowledge base on what kinds of stimuli are most effective at evoking responses is remarkably slim. A full quantitative understanding would require a detailed model of the electric fields that current pulses induce along axonal and somatic membranes, but in high density cultures, the arrangement of neurons and glia is too complex to construct such a model.…”

Development of a Neural Interface for PNS Motor Control

“…Fig. 2 A-B is a schematic of a neuron resting on top of an electrode in a planar electrode array [31]. Current can either be forced into the cell by the electrode, or cellular depolarizations can be detected by the electrode, depending on whether the electrode is stimulating or recording from the associated tissue.…”

“…This current is divided into a portion that flows from the cell to the underlying electrode and a portion that leaks out around its boundaries (through the sealing gap) and into the medium. The relative amount of current traveling via each of these two paths is a function of the membrane characteristics of the cell, the material characteristics of the electrode, and the resistance of the sealing gap (R seal ) [31]. A high R seal means that more of the current associated with the cellular depolarization is transmitted directly to the electrode (Fig.…”

Burst analysis of chemically stimulated spinal cord neuronal networks cultured on microelectrode arrays

“…The array used for our experiments [7] is made of glass with 60 gold microelectrodes, 40 of which used for acquisition (10 micron diameter). The 40 recording electrodes were subdivided into 5 groups of 8 electrodes each, directly connected with the amplifier via an 8 poles shielded cable.…”