Nachweis- und Bestimmungsgrenze beim direkt potentiometrischen Arbeiten mit ionensensitiven Elektroden

Summary

Calibration of ion-sensitive electrodes using nonlinear regression analysis is combined with an increase of the working range to lower concentrations. It is possible to have statistically reliable results lower than the so-called limit of determination according to IUPAC. From these items the critical level, the limit of detection and the limit of determination are derived by the calibration function, its inverse (the function of analysis) and the confidence interval. The limit of detection is defined by the smallest detectable signal and the calibration function. The limit of determination is defined by the smallest concentration of an analysis that will be statistically significant with a preset probability of error differentiated from the concentration zero and the blind value of the potentiometric measurement. The limit of determination is therefore the smallest concentration of analysis that may be quantitatively determined.