Publications by Olivier Frey | EPFL Graph Search

Multisite monitoring of choline using biosensor microprobe arrays in combination with CMOS circuitry

Nico de Rooij, Olivier Frey, Peter Van der Wal

A miniature device enabling parallel in vivo detection of the neurotransmitter choline in multiple brain regions of freely behaving rodents is presented. This is achieved by combining a biosensor microprobe array with a custom-developed CMOS chip. Each sil ...

De Gruyter2014

Biosensor microprobe arrays for in vivo monitoring of neurotransmitters

Olivier Frey

Real-time monitoring of neurotransmitters is of utmost importance for understanding the functioning of the brain. Especially L-glutamate and choline play a major role in chemical signalling and are highly involved in cognitive functions such as learning, m ...

EPFL2010

Microelectrode-array of IrO2 prepared by thermal treatment of pure Ir

Christos Comninellis, Stéphane Fierro, Agnieszka Kapalka, Olivier Frey

In this paper, the IrO2 electrode preparation technique consisting in thermal treatment of pure Ir in air was used in order to produce an IrO2-based microelectrode-array (TOIROF-MEA) with low capacitive background current. The TOIROF-MEA was characterized ...

Elsevier2010

Electrochemical behaviour of ammonia (NH4+/NH3) on electrochemically grown anodic iridium oxide film (AIROF) electrode

Christos Comninellis, Stéphane Fierro, Agnieszka Kapalka, Olivier Frey

The electrochemical behaviour of ammonia (NH4+/NH3) in sodium perchlorate at pH 9 has been investigated on electrochemically grown anodic iridium oxide film (AIROF) electrode. In base electrolyte at pH 9, the Ir(IV)/Ir(III) surface redox couple exhibits un ...

Elsevier2009

Electrochemical comparison between IrO2 prepared by anodic oxidation of pure iridium and IrO2 prepared by thermal decomposition of H2IrC16 precursor solution

Christos Comninellis, Stéphane Fierro, Lassine Ouattara, Olivier Frey

Surface redox activities, oxygen evolution reaction (OER), oxidation of formic acid (FA), and anodic stability were investigated and compared for IrO2 electrodes prepared by two techniques: the thermal decomposition of H2IrCl6 precursor (TDIROF) and the an ...

Springer Netherlands2009

Simultaneous Chemical Recording and Stimulation in the Brain Using an Assembly of Biosensor Silicon Microprobes and SU-8 Microinjectors

Nico de Rooij, Olivier Frey, Peter Van der Wal

In this contribution we present multi-channel microinjector arrays fabricated by a reliable three-layer SU-8 process and assembled with glutamate biosensor microprobes'. It enables local delivery of specific liquids into brain tissue for the stimulation or ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2009

Hybrid microfluidic cartridge formed by irreversible bonding of SU-8 and PDMS for multi-layer flow applications

Nico de Rooij, Sara Talaei, Olivier Frey, Peter Van der Wal

SU-8 and polydimethylsiloxane (PDMS) are both transparent materials with properties very convenient for rapid prototyping of microfluidic systems. However, previous efforts of combining these two materials failed due to poor adhesion between them. Herein, ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2009

Biosensor Microprobe Functionalisation Using an On-Chip Dispensing Approach

Nico de Rooij, Olivier Frey, Peter Van der Wal

Silicon biosensor microprobes for the in vivo detection of neurotransmitters are equipped with removable clips for an on-chip functionalisation technique that allows a simple and comfortable but very local and reproducible deposition of sensitive layers on ...

Elsevier Science, Reg Sales Off, Customer Support Dept, 655 Ave Of The Americas, New York, Ny 10010 Usa2009