TUBULAR POTENTIOMETRIC DETECTOR FOR FLOW-INJECTION BASED ON HOMOGENEOUS CRYSTALLINE MEMBRANES SENSITIVE TO COPPER, CADMIUM AND LEAD

Copper, cadmium and read potentiometric tubular detectors, based on homogeneous crystalline membranes obtained by high-pressure pressing of XS-Ag2S mixtures (X = Cu, Cd or Pb), were prepared and tested. Response characteristics (linear response range, limit of detection, stability and time of response, pH range and potentiometric selectivity coefficients) were established and compared with those of conventionally shaped electrodes prepared with the same membranes. The standards of performance of the tubular potentiometric detectors when used in low-dispersion manifolds were found to be similar to those of the corresponding conventional electrodes in batch conditions.