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The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin

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The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Doctoral Dissertations Graduate School 12-2017 The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin Mark Alan Moore University of Tennessee Follow this and additional works at: https://trace.tennessee.edu/utk_graddiss Recommended Citation Moore, Mark Alan, "The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin. " PhD diss., University of Tennessee, 2017. https://trace.tennessee.edu/utk_graddiss/4848 This Dissertation is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Doctoral Dissertations by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a dissertation written by Mark Alan Moore entitled "The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin." I have examined the final electronic copy of this dissertation for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Doctor of Philosophy, with a major in Chemical Engineering. Robert Counce, Major Professor We have read this dissertation and recommend its acceptance: Paul Dalhaimer, Howard Hall, George Schweitzer, Jack Watson Accepted for the Council: Dixie L. Thompson Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) The Separation of Bismuth-213 from Actinium-225 and the Ion Exchange Properties of the Alkali Metal Cations with an Inorganic Resin A Dissertation Presented for the Doctor of Philosophy Degree The University of Tennessee, Knoxville Mark Alan Moore December 2017 Copyright © 2017 by Mark A. Moore. All rights reserved. ii Acknowledgements This research was funded by a research grant from the National Nuclear Security Administration (NNSA) Stewardship Science Academic Alliances (SSAA) Program. All views expressed here are those of the author and do not necessarily reflect those of the NNSA or the SSAA. iii Abstract Interest in the use of alpha radiation emitters in radio immunotherapy is due to the high linear energy transfer and short range of alpha radiation. These properties enable the targeting of single tumor cells with diminished risk of damaging the surrounding tissue. Significant research has been done in the separation of the alpha emitter Bismuth-213 from its parent solution of Actinium-225 using organic resins. Due to radiolytic damage to the resin emphasis in the research has focused on the rapid elution of Bismuth-213 or storage of the parent Actinium-225 solution on a more robust resin. Inorganic ion exchange resins have shown a greater resistance to radiolytic damage than organic resins. If an inorganic resin could retain its structural integrity then Actinium-225 could be loaded on an inorganic resin bed with a clinical dose of Bismuth-213 eluted from the column when needed. The performance of two inorganic ion exchange resins, Isolute SCX and Isolute SCX-2, were compared to the performance of the organic resin AG-50X8 in the separation of the radionuclide Bismuth-213 from its parent solution of Actinium-225. Performance was based on the percent of Bismuth-213 available eluted, and the breakthrough of Actinium-225. It was found that Isolute SCX and Isolute SCX-2 produced less of the Bismuth-213 available on the column. The breakthrough of the Actinium-225 for all three columns was well below the toxicity level. Further tests showed that Isolute SCX and Isolute SCX-2 suffered less apparent damage from radiation generated in situ. A comparison of the ion exchange properties of the inorganic resin Isolute SCX-2 with alkali metal cations, including francium, to several better known organic resins is also presented. With hydrophobic organic ion exchange resins the selectivity of alkali metal cations tends to increase as the mass of the ion increases while the selectivity's for the less hydrophobic Isolute SCX-2 increased from francium to cesium to potassium to sodium. Lithium had the lowest selectivity, likely due to the strong hydration of the ion, and rubidium did not follow the selectivity trends of the other alkali ions. iv Table of Contents INTRODUCTION ..............................................................................................................................1 Scope .............................................................................................................................................2 Background ....................................................................................................................................2 Alpha Radiation and its Use in Cancer Treatment ..........................................................................2 213Bi ...........................................................................................................................................3 Francium ....................................................................................................................................3 AG-50X8, Isolute SCX, Isolute SCX-2 .........................................................................................5 Ion Exchange ..............................................................................................................................6 Gamma-Rays and Gamma-Ray Spectroscopy................................................................................7 References......................................................................................................................................9 CHAPTER I: THE ION EXCHANGE PROPERTIES OF THE ALKALI METAL CATIONS INCLUDING FRANCIUM WITH AN INORGANIC RESIN ............................................................. 10 Abstract ....................................................................................................................................... 11 Introduction.................................................................................................................................. 11 Background .............................................................................................................................. 11 Objective .................................................................................................................................. 11 Theory ...................................................................................................................................... 12 Experimental ................................................................................................................................ 12 Method for Stable Alkali Metal Cations ...................................................................................... 13 Method for 221Fr ........................................................................................................................ 13 Results ......................................................................................................................................... 19 Discussion .................................................................................................................................... 20 Conclusion ................................................................................................................................... 23 References.................................................................................................................................... 24 CHAPTER II: THE PERFORMANCE OF TWO SILICA BASED ION EXCHANGE RESINS IN THE SEPARATION OF 213BI FROM ITS PARENT SOLUTION OF 225AC ................................................ 25 Abstract ....................................................................................................................................... 26 Introduction.................................................................................................................................. 26 Background .............................................................................................................................. 26 Objective .................................................................................................................................. 27 Experimental ................................................................................................................................ 27 Materials................................................................................................................................... 27 Method ..................................................................................................................................... 27 Results and Discussion .................................................................................................................. 29 213Bi Production ........................................................................................................................ 29 Breakthrough of 225Ac................................................................................................................ 30 Distribution Coefficients and Separation Factors ......................................................................... 30 Elution Curves .........................................................................................................................
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