Tuned galvanostatic polarization of solid-state lead-selective electrodes for lowering of the detection limit

Lowering of the detection limit of solid-state lead-selective electrodes was achieved by using the tuned galvanostatic polarization method. A Nernstian response was obtained down to nanomolar concentrations (low detection limit 10(-9) mol dm(-3) Pb2+). Good repeatability of the calibration curves was achieved by using a well established measuring procedure. Relatively high cathodic current densities were applied to the solid-state membrane in order to shorten the measurement time. Successful determination of lead in a synthetic sample (pPb(2+) = 7.97 +/- 0.08) was achieved by introducing an analytical protocol and favourably compared to inductively coupled plasma mass spectrometry (pPb = 7.93). By applying this method, a significant improvement in the detection limit of solid-state lead-selective electrodes was attained. (C) 2011 Elsevier BM. All rights reserved.