Parallel On-Chip Analysis of Single Vesicle Neurotransmitter Release

Abstract

Real-time investigations of neurotransmitter release provide a direct insight on the mechanisms involved in synaptic communication. Carbon fiber microelectrodes are state-of-the-art tools for electrochemical measurements of single vesicle neurotransmitter release. Yet, they lack high-throughput capabilities that are required for collecting robust statistically significant data across multiple samples. Here, we present a chip-based recording system enabling parallel in vitro measurements of individual neurotransmitter release events from cells, cultured directly on planar multielectrode arrays. The applicability of this cell-based platform to pharmacological screening is demonstrated by resolving minute concentration-dependent effects of the dopamine reuptake inhibitor nomifensine on recorded single-vesicle release events from PC12 cells. The experimental results, showing an increased half-time of the recorded events, are complemented by an analytical model for the verification of drug action.

Stochastic On-Chip Detection of Subpicomolar Concentrations of Silver Nanoparticles

“…A detailed description of the system can be found elsewhere. 19 Briefly, the system consists of a preamplifying 64-channel head stage, followed by a main amplifier and an ADC converter (NI USB 6255, National Instruments). The output of the preamplifier stage used in these experiments was 1 mV/pA and subsequently amplified by a factor of 100 by the main amplifier.…”

Understanding nano-impacts: impact times and near-wall hindered diffusion

“…31 With respect to the here discussed theoretical model, we can interpret the game as a onedimensional random walk of a nanoparticle on a grid in z direction: a then represents the initial position z 0 of the nanoparticle inside a region featuring two boundaries at the grid points 0 and a + b. The distance between two grid points features a length of dz and the particle is randomly displaced by one gridpoint at the frequency (dt) À1 , while dz and dt are related via eqn (4).…”

Nanocavity crossbar arrays for parallel electrochemical sensing on a chip

“…Hereby, one bar electrode is swept from −200 mV to 600 mV and then sweept reverse from 600 mV to −200 mV at a rate of 80 mV/s, while the corresponding other electrode(s) remain at a reducing potential of −200 mV. Parallel redox cycling amperometric measurements for electrochemical imaging are performed by using a custom-built amplifier system (picoAmp64) [36]. The electrodes are set to constant potentials of either −200 mV or 600 mV.…”