Spatial Investigation of Analytes at the Sampling Cone of an ICP-MS

To improve the sensitivity of an inductively coupled plasma mass spectrometer (ICP-MS), the analytes ions must be transmitted from the plasma through the interfacial region as efficient as possible. Understanding transport behaviors of analytes from the plasma through the sampling cone require knowledge of analytes spatial distributions at the tip of the sampling cone. Relying on laser induced fluorescence technique, the temperature variations of the plasma and spatial distribution of barium at the tip of the sampling cone of an ICP under a seris of experimental conditions were investigated. The result shows that ICP incident power and nebulizer flow have significant impact on the atomization and ionization of analytes. However, higher ICP incident power does not mean higher efficiency of analytes reaching the sampling cone. The results can provide some guides to design improvement of a commercial ICP-MS.