Potentiometric Differential Microdetector With Interchange Solid Membranes Used in Flow Injection Analysis

Abstract

The construction and characteristics of two potentiometric differential microdetectors equipped with two similar ion-selective membranes are described. The two membranes used were of Ag₂S for Ag^I and S^2- and CuS–Ag₂S for Cu^II. The active volume of the measuring cell was about 3 µl. Calibration plots were linear, with almost theoretical slopes, down to 10^-6 mol dm^-3 Ag^I, 5 × 10^-6 mol dm^-3 Cu^II and 10^-5 mol dm^-3 S^2-. The throughput was 40–60 samples h^-1 depending on the sample. The errors in the determination of the above-mentioned ions were below 3.9%.

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