MICROFABRICATED ONLINE SENSOR FOR CONTINUOUS MONITORING OF L-GLUTAMATE

Citation
O. Niwa et al., MICROFABRICATED ONLINE SENSOR FOR CONTINUOUS MONITORING OF L-GLUTAMATE, Analytical sciences, 14(5), 1998, pp. 947-953
Citations number
42
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Chemistry Analytical
Journal title
ISSN journal
0910-6340
Volume
14
Issue
5
Year of publication
1998
Pages
947 - 953
Database
ISI
SICI code
0910-6340(1998)14:5<947:MOSFCM>2.0.ZU;2-S
Abstract
An on-line sensor was developed by using a micro-machining technique f or the continuous measurement of extracellular glutamate. The sensor w as made by bonding two glass plates together. One of the plates has a rectangular flow channel which is connected to both a sampling and an outlet capillary. The other has a carbon film-based electrochemical ce ll, which consists of an enzyme-modified electrode surrounded by polym er film to form a thin-layer-channel flow cell. The sensor has a high analyte conversion efficiency due to the cell structure. As a result, we obtained a low detection limit of 44 nM (S/N=3). The cathodic curre nt started to increase about 10 s after sample introduction at a flow rate of 2 mu l/min due to its small inner volume. Using the sensor, we can monitor the extracellular L-glutamate increase caused by stimulat ing it with KCl and gamma-aminobutyric acid (GABA) by locating the sam pling capillary very close to the cell.