Rapid method for the determination of trace fluoride and activation of ion-selective electrode.
A method for activating ISE is proposed that can allow determination of the fluoride concentration at ng mL(-1) level with good precision and accuracy. Fluoride ISE is activated in 0.5 mol L(-1) HClO4 medium and then fluoride is determined in the same medium. The linear range for the determination of fluoride is between 1.00 x 10(-2)-1.00 x 10(-7) mol L(-1), and the detection limit of the method is 1.0 ng mL(-1). The advantage of this method is that it is free from the use of TISAB solution while being, time-saving and labor-saving. A mechanism study of the activation of FISE in HClO4 medium is explained. The method has been used for the determination of trace fluoride in milk and flour with satisfactory results.
Shi
Sheng-xun
SX
College of Chemistry and Environmental Science, University of Hebei, Baoding 071002, China. ransuo@yahoo.com.cn
Zhu
Zhi-guang
ZG
Suo
Ran
R
Wang
Chun
C