Novel biological, forensic, and historical applications of inductively coupled plasma-mass spectrometry

Abstract

<p>This dissertation describes three new applications of inductively coupled plasma mass spectrometry (ICP-MS).</p> <p>Arsenic content was measured in rice and coffee samples. These results for the concentration of arsenic in rice and coffee independently verify the results of a similar FDA study. Direct comparisons of the arsenic content in different types of rice (i.e. black, brown, jasmine) indicated no correlation in the amount of arsenic and the type of rice. Additionally, the rice and coffee samples were cultivated in different locations throughout the world and results were analyzed to discern any trends between the amount of arsenic and the country of origin.</p> <p>Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is used to measure the trace elemental composition of various well-known brands of duct and electrical tapes. A new method derived from existing chemometric principles (principal components analysis) for identifying which elements vary the most between the brands of tape is described. The new method is applied to measurements collected from duct and electrical tapes and they are compared to one another.</p> <p>Pigments from a ship which sank off the coast of Texas in 1684 were recently recovered. ICP-MS was used to perform elemental analysis on these samples to identify the type of pigment. These pigments were suspected to be products for trade with natives in the new world. As was common at the time, the pigments were also suspected of adulteration (being cut with a cheaper product); they were analyzed for evidence of such a practice.</p> <p>ICP-MS is one of the most sensitive useful tools for elemental analysis. Knowing the exact composition of various samples using this technique can help scientists assist in setting new public safety standards in the present, provide new techniques for the future, and learn about life in the past. The three applications highlight the versatility of ICP-MS to a broadening number of different scientific disciplines.</p>