DMA as a Gas Converter from Aerosol to "Argonsol" for Real-Time Chemical Analysis Using ICP-MS

In this study, "Argonsol" is defined as an assembly of liquid or solid particles suspended in argon, just as an aerosol is a suspension in air. Argonsol can be generated by a nebulizer and fed into a plasma torch for measurement by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS). We have developed a new gas-conversion method, by means of a DMA, from normal aerosol to size-classified Argonsol for a chemical analysis using ICP-MS. A test aerosol containing lead as a typical toxic heavy metal was introduced into this system. With this system the size-related elemental concentration of lead nitrate particles in the range of 30 to 140 nm was measured. The sensitivity of this system is better than fg (10 -15 g) of lead in the total mass of particles introduced into ICP-MS. In principle, it is possible for our system to analyze all the elements that ICP-MS and/or ICP-AES can analyze.