Disposable cholinesterase biosensor for the detection of pesticides in water-miscible organic solvents

Citation
T. Montesinos et al., Disposable cholinesterase biosensor for the detection of pesticides in water-miscible organic solvents, ANALYT CHIM, 431(2), 2001, pp. 231-237
Citations number
13
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
ANALYTICA CHIMICA ACTA
ISSN journal
00032670 → ACNP
Volume
431
Issue
2
Year of publication
2001
Pages
231 - 237
Database
ISI
SICI code
0003-2670(20010315)431:2<231:DCBFTD>2.0.ZU;2-3
Abstract
A disposable cholinesterase biosensor based on screen-printed electrodes wa s assembled and used to assess the effect of miscible organic solvents on t he acetylcholinesterase activity and on the inhibitory effect of organophos phorus pesticides on acetylcholinesterase activity. Acetonitrile, ethanol a nd DMSO were tested in a range 0-30% mixed with phosphate buffer (0.1 M, pH 7). With 5% acetonitrile and 10% ethanol, an increase of the recorded curr ent was observed. The addition of 0.2% polyethylenimine to the enzyme prepa ration, before immobilisation, allowed the utilisation of 15% acetonitrile without negative effect on the enzyme activity. An inhibition calibration c urve was obtained using chlorpyrifos-ethyl-oxon, a compound widely used for agricultural purposes. The lowest detectable amount was 1 ppb following an incubation time of 10 min. The use of 5% acetonitrile and 0.2% polyethylen imine did not interfere with the enzyme-inhibitor interactions. (C) 2001 El sevier Science B.V. All rights reserved.