Volatile Species in Inductively Coupled Plasma Atomic Emission Spectroscopy: Implications for Enhanced Sensitivity

We propose a sample introduction method involving the formation of volatile species in solution and subsequent pneumatic nebulization for inductively coupled plasma atomic emission spectrometry. A study of osmium oxidized to OsO4 and preliminary results for mercury reduced to the elemental form suggest that enhancements in sensitivity by a factor of 10 to 100 are achievable without degradation in analytical precision, in comparison with pneumatic nebulization of solutions containing the element of interest in a nonvolatile form. We discuss the physical basis for the method and support it by a brief theoretical treatment. The technique promises a broad applicability to elements capable of existing in a volatile form in solution. For the elements studied, no modifications of a commercial ICP spectrometer or sample introduction system are required.