Cyclodextrin Solutions

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Cyclodextrin Solutions University of Rhode Island DigitalCommons@URI Open Access Master's Theses 2020 METHODS IN THE DETECTION OF ALIPHATIC ALCOHOLS AND ANABOLIC STEROIDS IN β‑CYCLODEXTRIN SOLUTIONS Anna Zocchi Haynes University of Rhode Island, [email protected] Follow this and additional works at: https://digitalcommons.uri.edu/theses Recommended Citation Haynes, Anna Zocchi, "METHODS IN THE DETECTION OF ALIPHATIC ALCOHOLS AND ANABOLIC STEROIDS IN β‑CYCLODEXTRIN SOLUTIONS" (2020). Open Access Master's Theses. Paper 1862. https://digitalcommons.uri.edu/theses/1862 This Thesis is brought to you for free and open access by DigitalCommons@URI. It has been accepted for inclusion in Open Access Master's Theses by an authorized administrator of DigitalCommons@URI. For more information, please contact [email protected]. METHODS IN THE DETECTION OF ALIPHATIC ALCOHOLS AND ANABOLIC STEROIDS IN β‑CYCLODEXTRIN SOLUTIONS BY ANNA ZOCCHI HAYNES A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN CHEMISTRY UNIVERSITY OF RHODE ISLAND 2020 MASTER OF SCIENCE OF ANNA ZOCCHI HAYNES APPROVED: Thesis Committee: Major Professor Mindy Levine William Euler Geoffrey Bothun Nasser H. Zawia Dean of the Graduate School UNIVERSITY OF RHODE ISLAND 2020 ABSTRACT The sensitive, selective, and practical detection of aliphatic alcohols is a continuing technical challenge with significant impact in public health work and environmental remediation efforts. Reported in the first manuscript is the use of a β-cyclodextrin derivative to promote proximity-induced interactions between aliphatic alcohol analytes and a brightly colored organic dye, which result in highly analyte-specific color changes that enabled accurate alcohol identification. Linear discriminant analysis of the color changes enabled resulting in 100% differentiation of the colorimetric signals obtained from methanol, ethanol, and isopropanol in combination with BODIPY and Rhodamine dyes. The resulting solution-state detection system has significant broad-based applicability because it uses only easily available materials to achieve such detection, with moderate limits of detection obtained. Future research with this sensor system will focus on decreasing limits of detection as well as on optimizing the system for quantitative detection applications. Reported in Chapter 2 of this thesis are our efforts towards the development of similar cyclodextrin-based systems for the detection of anabolic steroids that are of interest in illegal doping scandals. These systems, in close analogy to other systems developed in our group, rely on the fact that combining the target analytes with a high quantum yield fluorophore results in a measurable, analyte-specific change in the fluorophore emission signal. Promising results were seen in our solution-state detection of anabolic steroids via the use of β-cyclodextrin derivatives as supramolecular scaffolds and Rhodamine 6G as the signal transducing element. Using linear discriminant analysis, arrays were generated, illustrating the differentiation and classification of the analytes with high selectivity in the system. Limits of detection falling below the micromolar range show a high sensitivity of the system. Current efforts are focused on improving the reproducibility of these experiments to enable a high functioning detection system as well as efforts toward moving to a solid-state detection system. ACKNOWLEGMENTS I would first like to thank the University of Rhode Island for granting me the opportunity to follow my passion of chemistry into graduate school. I would specifically like to thank the faculty members of the chemistry department who have never failed to point me in the right direction toward my success and showing me endless possibilities for my education and career. To Dr. Mindy Levine, thank you for finding a space in such a great group, advising me from Israel and allowing me to take my ideas and run with them. I have become to trust my own thoughts on what my science is illustrating which has shaped and guided the research I have done these past two years. Thank you to all of the past members of the Levine group that have offered support and guidance no matter where they have found themselves. A special thank you to Dr. Teresa Mako and Joan Racicot for answering all of my never-ending questions, giving me the confidence to step out of my comfort zone and never failing to show their support for whatever my next step is. To all the friends that I have made throughout my time at URI, thank you for reminding me to have fun every once in a while, even if it is just a trip to grab some ice cream or a Target run. Lastly, I would like to thank my family. It is not an exaggeration to say that I would not have achieved this much without you. To my mum and dad, thank you for always picking up the phone to talk to me, even if you’re in the middle of making pasta. Thank you for showing me what true dedication and passion is and for never letting me forget that you’re proud of me. To Alex, thank you for always lending your ear to my smallest problems and giving me a hug when you know I need it most. To Heather, Paul and PJ, thank you for your constant reminder that I can do this and never failing to make me laugh (as long as I didn’t let the facts get in the way of the joke). iv PREFACE This thesis is presented in manuscript format according to the guidelines of the graduate school of the University of Rhode Island. Two manuscripts will be presented in this thesis. Chapter 1 is published in ACS Omega with authors Anna Haynes, Priva Halpert, and Mindy Levine. Chapter 2 is being submitted for publication to RSC Advances with authors Anna Haynes and Mindy Levine. v TABLE OF CONTENTS ABSTRACT ....................................................................................................................... ii ACKNOWLEGMENTS .................................................................................................. iv PREFACE .......................................................................................................................... v TABLE OF CONTENTS ................................................................................................ vi LIST OF TABLES .......................................................................................................... vii LIST OF FIGURES .......................................................................................................... x CHAPTER 1 ...................................................................................................................... 1 ABSTRACT ................................................................................................................... 2 INTRODUCTION ......................................................................................................... 2 EXPERIMENTAL SECTION ..................................................................................... 5 RESULTS AND DISCUSSION.................................................................................... 9 CONCLUSIONS ......................................................................................................... 18 REFERENCES ............................................................................................................ 19 ELECTRONIC SUPPLEMENTARY INFORMATION ........................................ 23 CHAPTER 2 .................................................................................................................... 48 ABSTRACT ................................................................................................................. 49 INTRODUCTION ....................................................................................................... 49 EXPERIMENTAL SECTION ................................................................................... 51 RESULTS AND DISCUSSION.................................................................................. 53 CONCLUSION ............................................................................................................ 64 ACKNOWLEDGEMENTS ........................................................................................ 65 REFERENCES ............................................................................................................ 66 ELECTRONIC SUPPLEMENTARY INFORMATION ........................................ 70 vi LIST OF TABLES Table 1: Concentration of cyclodextrins and dyes in solution.a ......................................... 6 Table 2: Cumulative proportions of total dispersion for each cyclodextrin with dye 4 and 5.a ......................................................................................... 10 Table 3: Percent correct classification values obtained from Jackknifed Classification analysis of the arrays.a ............................................................. 12 Table 5: LODs and LOQs of each alcohol with dyes 4 and 5 in the presence of 2-HP-β-CD. ................................................................................................... 17 Table 6: LODs and LOQs of isopropanol with increased concentrations of dye 4 and 5 and 2-HP-β-CD. ............................................................................................ 17 Table 7. Concentration of Dyes in Solution ..................................................................... 25 Table 8. Volume to Mass Conversions of Cyclodextrins and Final Concentrations ....... 25 Table 9. Amount of Alcohol Added
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