Influence of aerosol desolvation from the ultrasonic nebulizer on the matrix effect in axial view inductively coupled plasma atomic emission spectrometry

In this study, the implications of water loading into the central channel o f the plasma were considered when an ultrasonic nebulizer (USN) associated with desolvation was used in axial-view inductively coupled plasma atomic e mission spectrometry. The effects have been characterised during cadmium an alysis in the presence of various environmental matrix types. Interferences occurred as a result of changes in the sample introduction system. Signal suppression was observed for the highest water loading. Conversely, signal enhancement occurred for the lowest water loading. The desolvation of aeros ols in USN saved the plasma a lot of energy but influenced the excitation c onditions by changing the thermal environment of the plasma. From the resul ts shown in this paper, it was clear that the behaviour of a solvent remova l system depended on the operating conditions used (concentration of matrix , temperature heating and cooling and especially carrier gas flow rate). Un der a rigorous choice of these factors according to the nature of the sampl e matrix, the interferences could be minimised. The plasma characteristics dependent on the concentration of water have also been evaluated with the d iagnostic MgII/MgI line intensity ratio, which confirm the previous results .