title: On-chip multi-electrochemical sensor array platform for simultaneous screening of nitric oxide and peroxynitrite.
abstract: In this work we report on the design, microfabrication and analytical performances of a new electrochemical sensor array (ESA) which allows for the first time the simultaneous amperometric detection of nitric oxide (NO) and peroxynitrite (ONOO(-)), two biologically relevant molecules. The on-chip device includes individually addressable sets of gold ultramicroelectrodes (UMEs) of 50 µm diameter, Ag/AgCl reference electrode and gold counter electrode. The electrodes are separated into two groups; each has one reference electrode, one counter electrode and 110 UMEs specifically tailored to detect a specific analyte. The ESA is incorporated on a custom interface with a cell culture well and spring contact pins that can be easily interconnected to an external multichannel potentiostat. Each UME of the network dedicated to the detection of NO is electrochemically modified by electrodepositing thin layers of poly(eugenol) and poly(phenol). The detection of NO is performed amperometrically at 0.8 V vs. Ag/AgCl in phosphate buffer solution (PBS, pH = 7.4) and other buffers adapted to biological cell culture, using a NO-donor. The network of UMEs dedicated to the detection of ONOO(-) is used without further chemical modification of the surface and the uncoated gold electrodes operate at -0.1 V vs. Ag/AgCl to detect the reduction of ONOOH in PBS. The selectivity issue of both sensors against major biologically relevant interfering analytes is examined. Simultaneous detection of NO and ONOO(-) in PBS is also achieved.
authors.affiliation: Unité de Pharmacologie Chimique et Génétique et Imagerie, CNRS 8151, École Nationale Supérieure de Chimie de Paris, Chimie ParisTech, Université Paris Descartes, Paris, France.
authors.forename: Damien
authors.initials: D
authors.lastname: Quinton
authors.forename: Aurélie
authors.initials: A
authors.lastname: Girard
authors.forename: Loan To
authors.initials: LT
authors.lastname: Thi Kim
authors.forename: Vincent
authors.initials: V
authors.lastname: Raimbault
authors.forename: Laurent
authors.initials: L
authors.lastname: Griscom
authors.forename: Florence
authors.initials: F
authors.lastname: Razan
authors.forename: Sophie
authors.initials: S
authors.lastname: Griveau
authors.forename: Fethi
authors.initials: F
authors.lastname: Bedioui
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D004563:Electrochemistry; D004867:Equipment Design; D056656:Lab-On-A-Chip Devices; D008839:Microelectrodes; D009569:Nitric Oxide / Q000032:analysis* / Q000737:chemistry; D030421:Peroxynitrous Acid / Q000032:analysis* / Q000737:chemistry; D013997:Time Factors
chemical_list: D030421:Peroxynitrous Acid; D009569:Nitric Oxide