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Updated: Jun 12, 2026
Fabrication of Carbon Nanotube High-Frequency Nanoelectronic Biosensor for Sensing in High Ionic Strength Solutions
Published on: July 22, 2013
Determination of calcium ion in sap using carbon nanotube-based ion-selective electrodes
Rafael Hernández1, Jordi Riu, F Xavier Rius
1Department of Analytical and Organic Chemistry, Universitat Rovira i Virgili, Campus Sescelades, C/Marcel.lí Domingo s/n, 43007 Tarragona, Catalonia, Spain.
Abstract:
A new reduced-size solid-state electrode using carbon nanotubes as the transducing layer has been developed for the direct determination of Ca(2+) in sap, overcoming problems encountered by commercial ISEs analysing real complex samples. We show that this solid-contact ISE, which can be easily miniaturized, can be used directly in diluted real samples without any other pretreatment. The performance parameters of the new ISE include a Nernstian slope and excellent stability, good coefficients of selectivity, range of linearity (10(-5) to 10(-2.5) M) and limit of detection (10(-6.2) M), thus making it an excellent tool for determining Ca(2+) in a wide range of plant species.
