Novel multicommuted flow manifold dedicated to the integrated calibration method

Abstract

Integrated calibration method (ICM) is one of the novel approaches in the field of analytical calibration. ICM enables several (e.g., six) estimates of an analytical result to be obtained in a single calibration procedure. These values respond differently and independently to errors caused by interference and non-linearity effects, thus making it possible to: (a) determine the accuracy of the analytical results, (b) detect interference effects in a sample, and (c) find an adequate way to eliminate the interference effect and to obtain results with improved accuracy. The presented work details the construction of a novel multicommuted flow manifold designed for realization of ICM, along with its operating rules. Accuracy and repeatability of the system were examined via spectrophotometric determination of chromium(III), and the obtained results are shown. Moreover, ICM used in this novel way was tested to verify the presence of, and to eliminate, systematic errors in the case of selenium determination, by using hydride generation-atomic fluorescence spectrometry (HG-AFS) in the presence of copper as an interferent. The procedure was also investigated for three real samples containing selenium, namely a diet supplement in the form of tablets, an energy drink and natural thermal water.