CONSTRUCTION AND EVALUATION OF A CRYSTALLINE SILVER DOUBLE-MEMBRANE TUBULAR POTENTIOMETRIC DETECTOR FOR FLOW-INJECTION ANALYSIS - APPLICATION TO CHLORIDE DETERMINATION IN WINE

This paper describes the construction and assessment of the operating characteristics and analytical usefulness of a homogeneous crystalline silver double membrane tubular electrode with increased sensitivity. The constructed electrodes allowed Ag(I) determinations in the 3 10(-5 ) - 1 10(-1) M range with a calibration slope of 114 mV dec(-1) and wi th good reproducibility (0.6 mV). The development and application of a flow injection analysis system manifold for chloride determinations i n wine samples, in a wide concentration range (10 - 800 mg L-1), with a titrant consumption of 90 mu g determination(-1) is also described. The results obtained from the analysis of 12 wine samples showed good agreement between the proposed method and the reference one, accomplis hing 90 - 200 samples h(-1).