title: Nanocavity redox cycling sensors for the detection of dopamine fluctuations in microfluidic gradients.
abstract: Electrochemical mapping of neurotransmitter concentrations on a chip promises to be an interesting technique for investigating synaptic release in cellular networks. In here, we present a novel chip-based device for the detection of neurotransmitter fluctuations in real-time. The chip features an array of plane-parallel nanocavity sensors, which strongly amplify the electrochemical signal. This amplification is based on efficient redox cycling via confined diffusion between two electrodes inside the nanocavity sensors. We demonstrate the capability of resolving concentration fluctuations of redox-active species in a microfluidic mixing gradient on the chip. The results are explained by a simulated concentration profile that was calculated on the basis of the coupled Navier-Stokes and convection-diffusion equations using a finite element approach.
authors.affiliation: Institut für Bio- und Nanosysteme (IBN), Forschungszentrum Jülich GmbH, 52425 Jülich, Germany.
authors.forename: Enno
authors.initials: E
authors.lastname: Kätelhön
authors.forename: Boris
authors.initials: B
authors.lastname: Hofmann
authors.forename: Serge G
authors.initials: SG
authors.lastname: Lemay
authors.forename: Marcel A G
authors.initials: MA
authors.lastname: Zevenbergen
authors.forename: Andreas
authors.initials: A
authors.lastname: Offenhäusser
authors.forename: Bernhard
authors.initials: B
authors.lastname: Wolfrum
mesh_terms: D004298:Dopamine / Q000032:analysis*; D046228:Microarray Analysis / Q000379:methods*; D044085:Microfluidics / Q000379:methods*; D049329:Nanostructures / Q000737:chemistry*; D010084:Oxidation-Reduction
chemical_list: D004298:Dopamine