MONODISPERSE DRIED MICROPARTICULATE INJECTOR - A NEW TOOL FOR STUDYING FUNDAMENTAL PROCESSES IN INDUCTIVELY-COUPLED PLASMAS

Spatially and temporally resolved inductively coupled plasma (ICP) emission intensities produced when samples are introduced by the monodisperse dried microparticulate injector (MDMI) are reported for the first time. The MDMI produces monodisperse droplets of controllable size on demand and reproducibly introduces the droplets into an ICP with 100% efficiency. Emission intensity peak heights and peak areas (in time) had a relative standard deviation of 1-6% except near the point of analyte particle vaporization. Sr atom emission intensity appears to be high only when the analyte particle is being vaporized. Analyte particle vaporization times were less than 80 mu s. By variance of the furnace temperature and the gas flow rate through the furnace, the drop size can be controlled. The height in the plasma where analyte particle vaporization occurs can be controlled from below the load coil to more than 30 mm above the load coil.