Sample preparation and sample introduction for inductively coupled plasma - mass spectrometry and inductively coupled plasma - atomic emission spectroscopy.

摘要

Inductively coupled plasma---mass spectrometry (ICP-MS) and inductively coupled plasma---atomic emission spectroscopy (ICP-AES) are routinely used for trace elemental analysis and as part of hyphenated systems used to perform speciation analyses. However, before the capabilities of these techniques can be fully realized, improvements must be made in the areas of sample preparation and sample introduction. This dissertation details work on the development of microwave sample preparation techniques and the utilization of low flow nebulizers for applications involving ICP-MS.; Microwave assisted extraction (MAE) was utilized to extract arsenic species from fish prior to speciation analysis using liquid chromatography coupled with ICP-MS. Arsenic was quantitatively extracted from a standard reference material using a methanol-water solution. Fish fillets purchased from a local store were also analyzed.; Microwave digestion with nitric acid was used to digest mouse tissue for the analysis of silicon by ICP-AES. This work was done as a collaborative project to investigate the mechanism behind silicone dissemination in vivo and to determine if the blood protein fibrinogen plays a significant role in this process. Mice receiving a single, peritoneal injection of a poly(dimethylsiloxane) emulsion were sacrificed, and their tissues were analyzed for total silicon. Tissues from mice having normal levels of fibrinogen, reduced levels of fibrinogen, and no fibrinogen were analyzed.; Liquid sample introduction is a serious concern when using ICP techniques. The performance of two low flow nebulizers and a standard glass concentric nebulizer were compared for use with ICP-MS and chromatographic mobile phases containing large concentrations of methanol. This was done in an attempt to see if the advantage of increased sample transport efficiency associated with low flow nebulizers would be fully realized when large quantities of methanol were present in the mobile phase.; A low flow nebulizer was also used to interface capillary electrophoresis to an ICP-MS. Metalloporphyrin species were separated using capillary electrophoresis and were detected using either ultraviolet detection or ICP-MS detection. ICP-MS offers the advantage of being an element specific technique, so complete resolution between species containing different metal atoms was not necessary.