Investigation of inorganic ions and organic acids in atmospheric aerosol by capillary electrophoresis

Abstract

In this paper capillary electrophoresis was applied for the analysis of inorganic cations and simultaneous investigation of inorganic anions and organic acids in atmospheric aerosol samples. Each method was developed for the characteristic matrix composition of atmospheric aerosol. Optimization of the composition of the background electrolytes, comparison of constant voltage and constant current separation modes, selection of the best detection wavelengths and investigation of the matrix effect of inorganic anions on the separation of organic acids were carried out. Simultaneous determination of inorganic anions and organic acids was achieved by using chromate as UV absorbing carrier ion in the running buffer. Reliability of the analysis of anions in the extracts of wide concentration range was improved by using constant current separation mode. Precision of the methods for migration time and peak area was found to be better than 0.5% and 2%, respectively. The results obtained by the analytical methods yield useful data for atmospheric physics and chemistry.