Date of Award
Doctor of Philosophy
The application of Pulsed Amperometric Detection (PAD) to inorganic and organic sulfur compounds is shown to be feasible at noble metal electrodes in aqueous solutions in conjunction with Flow-Injection (FI) and High Performance Liquid Chromatography (HPLC) analyses. Results are illustrated for inorganic sulfur anions detected at Pt and Au in alkaline solutions. Chromatographic separation and calibration of S('2-), SO(,3)('2-) and S(,2)O(,3)('2-) in alkaline solution was achieved. Detection limits were determined to be <5 ppm for each anion;Organic sulfur compounds also are detectable using PAD at Pt and Au. A theoretical basis is given for understanding the adsorption behavior of thiourea on Pt and Au. Linearization of calibration curves is discussed and illustrated for thiourea, and a detection limit was found to be 0.38 ppb using FI/PAD. Representative chromatograms are shown for mixtures containing thioureas, thioamides, thiophenes and dithiocarbamates. Calibration of the later two classes of compounds was achieved for HPLC/PAD and detection limits were determined to be <10 ppm and <85 ppm, respectively;Sulfur containing boron polyhedrals, which other laboratories have used in combination with Boron Neutron Capture Therapy (BNCT) to irradiate cancerous brain tumors, are shown to be quantitatively determined using FI and HPLC with PAD. Calibration and chromatographic separation of B(,12)H(,12)SH('2-), B(,12)H(,11)SSH(,11)B(,12)('4-) and B(,12)H(,11)S(O)SH(,11)B(,12)('4-) are illustrated. Detection limits of sub-nmole quantities of all three compounds were achieved.
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Theresa Z. Polta
Polta, Theresa Z., "Pulsed Amperometric Detection of sulfur compounds at noble metal electrodes in aqueous solutions" (1986). Retrospective Theses and Dissertations. 8290.