Characterization of an Inductively Coupled Plasma with Xylene Solutions Introduced as Monodisperse Aerosols

The optimum operating parameters of the inductively coupled plasma (ICP) with organic solvents are different from those with aqueous solutions. With organic solvents, the ICP is operated at higher power to overcome plasma cooling due to the organic solvent, and aerosol desolvation is necessary in order to reduce solvent load into the plasma. The monodisperse dried microparticulate injector (MDMI) offers the possibility of controlling solvent load by controlling the frequency with which droplets are introduced into the plasma. A test solution that contained 0.5 mg/L Ba in xylene was used to study the influence of MDMI operating parameters on the behavior of the ICP with an organic solvent. The spatial and temporal distribution of the solvent in the ICP was determined for different droplet production frequencies and MDMI oven temperatures, and the optimum operating conditions were established. The best detection limit for Ba in xylene was 1.5 ng/mL, or 0.16 pg (in 200 droplets).