A novel microfluidic flow-injection analysis device with fluorescence detection for cation sensing. Application to potassium.
A microfabricated device has been developed for fluorimetric detection of potassium ions without previous separation. It is based on use of a fluorescent molecular sensor, calix-bodipy, specially designed to be sensitive to and selective for the target ion. The device is essentially made of a Y-shape microchannel moulded in PDMS fixed on a glass substrate. A passive mixer is used for mixing the reactant and the analyte. The optical detection arrangement uses two optical fibres, one for excitation by a light-emitting diode, the other for collection of the fluorescence. This system enabled the flow-injection analysis of the concentration of potassium ions in aqueous solutions with a detection limit of 0.5 mmol L(-1) and without interference with sodium ions. A calibration plot was constructed using potassium standard solutions in the range 0-16 mmol L(-1), and was used for the determination of the potassium content of a pharmaceutical pill. Figure Photography of the microfluidic channel showing the ridges in the PDMS substrate at the top of the channel.
Destandau
Emilie
E
D'Alembert Institute, ENS de Cachan, 61 avenue du Président Wilson, 94235 Cachan Cedex, France.
Lefèvre
Jean-Pierre
JP
Chouai Fakhr Eddine
Assia
A
Desportes
Serge
S
Jullien
Marie Caroline
MC
Hierle
Rolland
R
Leray
Isabelle
I
Valeur
Bernard
B
Delaire
Jacques Alexis
JA