Comparison of the effect of acetic acid with axially and radially viewed inductively coupled plasma atomic emission spectrometry: influence of the operating conditions

Abstract

Acetic acid was selected as a highly perturbing matrix for the comparison of matrix effects between axial and radial viewing modes in ICP-AES. The effect of acetic acid (5 and 10% v/v) on the intensities of various ionic lines in ICP-AES was studied under extreme operating conditions,i.e., robust and non-robust conditions. A cross-flow nebulizer associated with a double-pass spray chamber was chosen as a sample introduction system. The influence of the operating conditions on the Mg II 280 nm/Mg I 285 nm line intensity ratio was also studied. This work confirmed that, under so-called robust conditions, i.e., high rf power and low carrier gas flow rate, the acetic acid caused an enhancement of the signal intensity, regardless of the energy line and the viewing mode, which could be assigned to a change in the aerosol formation and transport. An increase in the solvent transport rate and a significant modification of the primary, and especially the tertiary, aerosol drop size distributions were observed in the presence of acetic acid. Hence, finer aerosols were obtained when acetic acid was present.