Journal
ANALYTICA CHIMICA ACTA
Volume 597, Issue 2, Pages 231-237Publisher
ELSEVIER
DOI: 10.1016/j.aca.2007.07.005
Keywords
ionophore-polypyrrole modified chip; partial least squares; electronic tongue; impedance measurements
Categories
Ask authors/readers for more resources
A stable immobilization of ionophores (INPHs) was achieved by selectively electropolymerizing overoxidized pyrrol on the working electrode surface. The optimal conditions found allowed the immobilization of a huge amount of INPH which remained its recognition properties. A single sensing chip, containing a generic INPH or an INPH mixture, was employed to the joint quantification of potassium, ammonium and sodium in fertilizer samples. Electrochemical impedance spectroscopy (EIS) and partial least square (PLS) regression were used to obtain and process the data, respectively. The sensing element (INPH) and the exposure time were optimized. The best results were obtained by using the dibenzo-18-crown-6 INPH after waiting for 60s. the time required to stabilize the impedimetric measurement. Taking into account that a single chip was employed, acceptable relative errors were obtained in the determination of potassium and ammonium (17% and 9%, respectively) in real fertilizer samples, also containing sodium. Although sodium concentration could not be estimated with precision, it had to be introduced into the calibration set data in order to model its interference with the other two ions. (C) 2007 Elsevier B.V. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available