Direct Introduction of Aqueous Samples into a Low-Powered Microwave-Induced Plasma for Atomic Emission Spectrometry

The direct introduction of aqueous samples into a low-power microwave plasma is achieved with the use of a highly efficient TM010 microwave plasma. A toroidal plasma is sustained in the cavity solely by the Ar gas output of the nebulizer. Samples from a concentric glass nebulizer/Scott type spray chamber are fed directly into the cavity with no desolvation apparatus. A toroidal plasma can be sustained from the output of the nebulizer while 1 mL/min water is being aspirated at power levels of 36 W. This plasma is characterized as an atom cell by the study of emission profiles, working curves, and limits of detection. Also, ionization and vaporization interferences that occur with the use of this plasma are discussed.