Flow cell with double slope factor for potentiometric determination of fluoride at low concentrations
Abstract
A simple and reliable double-cell device with three ion-selective membranes for fluoride determinations in a continuous-flow system with an increased slope factor is presented. The relative standard deviation for the analysis of environmental waters was 0.01–0.03 and the slope factor was 113–44 mV pF–1, depending on the fluoride concentration level; the sampling rate was 120 h–1.