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Based Nanoparticles for Applications in Oral Drug Delivery So Synthesis and Characterization of Drug-Containing, Polysaccharide- Based Nanoparticles for Applications in Oral Drug Delivery Sonal Mazumder Dissertation submitted to the faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy In Macromolecular Science and Engineering Richey M. Davis, Chairman Kevin J. Edgar Judy S. Riffle Nammalwar Sriranganathan Eugene Joseph June 27, 2013 Blacksburg, Virginia Keywords: polysaccharides, mixing, nanoprecipitation, cellulose derivatives, antibacterial, antiviral, nanoparticle, self-assembly, particle size distribution, crystallization, composition, drug delivery, release kinetics, oral systems Synthesis and Characterization of Drug-Containing, Polysaccharide-Based Nanoparticles for Applications in Oral Drug Delivery Sonal Mazumder ABSTRACT Amorphous solid dispersions of polysaccharide-drug nanoparticles were produced by a rapid precipitation process known as flash nanoprecipitation and the formulation process and properties of nanoparticles were investigated. In this thesis, several novel cellulose derivatives and a pullulan derivative were studied. Among these polymers, carboxymethyl cellulose acetate butyrate (CMCAB)-drug nanoparticles were investigated in detail. Previous work has shown that the presence of different chemical groups in CMCAB could aid in complexation with hydrophobic drugs with low solubility, forming an amorphous matrix which can increase the effective solubility and, hence, bioavailability of the drug in physiological conditions. An antibacterial drug and two less soluble anti-viral drugs were selected as model drugs for this study. A separate study was conducted with several other cellulose derivatives like cellulose acetate propionate adipates with two different degree of substitution 0.33 and 0.85 (CAP-Adp 0.33 and CAP-Adp 0.85), cellulose acetate sebacate (CA-320S Se) and butyl pullulan-6- carboxylate (BPC) polymers. The effect of polymer interaction with drug molecule on release of antiviral drugs was studied with these latter polymers. The purpose of this research was two-fold. First, the methodology for producing drug- polymer nanoparticles with well-defined particle size distributions was developed. Second, the factors affecting drug loading and release properties of these nanoparticles were investigated. The nanoparticles were processed using two methods of solvent removal and drying to investigate their effects on drug loading and particle size: (a) various combinations of rotary vacuum evaporation (rotavap) and acid-induced flocculation were used and (b), dialysis followed by freeze drying. Dynamic light scattering showed particle sizes were between 150-400 nm with polydispersity index values as low as 0.12. The antibiotic drug loading efficiencies ranged from 14-40%, whereas drug loading efficiency as high as 85 % was attained with the antiviral drug. The dissolution studies showed an increase in the solution concentration and release of the amorphous drug nanoparticles. The high glass transition temperature helped to stabilize the drug in an amorphous form, thus increasing the effective solution concentration of the drug in an aqueous medium. iii For my late grandfather: Shri Chittaranjan Majumder The beginning of knowledge is the discovery of something we do not understand. - Frank Herbert iv Acknowledgements My Ph.D. program experience was the most challenging, yet enjoyable and rewarding, academic experience of my life, because I like to learn. It was an overwhelming experience as it opened my world throughout the years. I have met a lot of wonderful people. I have had the privilege of working with Dr. Richey Davis, who was instrumental in helping me to complete my doctoral work. I sincerely thank him for his unending support and invaluable guidance throughout the period of my PhD. I am also indebted to Dr. Judy Riffle whose help, stimulating suggestions and encouragement helped me in all the time of research. I take the opportunity to express my deepest sense of gratitude to Dr. Kevin J. Edgar for his constructive criticism, endless help, and guidance during my period of my PhD work. It was a great pleasure to get input and advice from Dr. Eugene Joseph. I am very much grateful to Dr. Nammalwar Sriranganathan for his generous support and constant encouragement. I consider myself very fortunate to have been able to work with Dr. Ishwar K. Puri on several other projects and publications during my PhD. He has always encouraged me and given me confidence. While working with him I also got the privilege to work with Dr. Joseph Falkinham. He has my deepest gratitude for his extreme encouragement and guidance. I am also very thankful to Dr. Chris Cornelius for his input. I am also very thankful to my colleagues, particularly in Dr. Edgar’s group, for synthesizing some of the polymers and helping with release studies. They include Haoyu Liu, Junia Pereira and Hale Cigdem Arca. It was also a pleasure to work with Samantha Casterlow who executed cell and animal experiments with my nanoparticles. I acknowledge the help rendered by Bruce Orler, Rick Caudill, Stephen McCartney, Weinan Leng, in learning and operating several instruments. I am grateful to Mr. Jason Schroedl for helping with computer related problems. Thanks to Raquel Mejia Ariza and Sharavanan Balasubramaniam for incorporating me into the research group and for introducing me to many laboratory and experimental techniques. I am particularly indebted to Sharavanan for his endless help and support during my defense. I would like to thank my labmate Seyyed Mohammad Hossein Abtahi and my colleagues from Dr. Edgar and Dr. Riffle group for their help and keeping things interesting. v I would like to thank Riley Chan for his ability to fix just about anything and Angie Flynn, Nora Bentley, Tina Kirk, Mary Smith Jane, Cyndy Graham, Tammy Hiner Jo, Leslie Thornton- O’Brien, Shelley Johnson, Lois Hall, Dawn Maxey, Lisa Smith ,Ennis McCrery, Ruth Athanson, Graduate School and Cranwell International Center for their assistance with countless matters. A special thanks to Anne-Marie Bracken: your friendship and advice has touched me from the day I arrived at Virginia Tech. I also thank the following for financial support: National Science Foundation (DMR #0909065), Macromolecular Interfaces Institute Graduate Student Fellowship, Institute for Critical Technology and Applied Science (ICTAS), DuPont Chemical Company and Department of Engineering Science and Mechanics. My life at Virginia Tech is priceless and I am really fortunate to know wonderful people here. I would like to thank Naresh, who has supported me through thick and thin- he had been a great friend, philosopher and guide. I thank Monrudee, whose care and support always motivated me. I am extremely thankful to my colleagues of my dance group-Dancilla and entire Blacksburg Indian community. I would like to thank my committee (2010-2011) and members of Indian Students Association in Virginia Tech. I am also very thankful to the members of Graduate Student Assembly (GSA), College of Engineering Graduate Student Committee (COEGSC) and ASHA for Education. I have gained immense experience and learnt various leadership and teamwork qualities while working with them. Sincerest thanks to my father, Dhananjoy Mazumder, and mother, Jayashri Mazumder, for being such wonderful parents providing constant support and encouragement. Thanks to my brother, Joydeep Mazumder, for everything. I must thank Anish Kumar Pramanik, for all his support and encouragement. Thanks for respecting my dreams and helping me to fulfill them. I thank Rajib Dey for his immense support and constant guidance as a teacher, a colleague and a friend. Thanks to my friends in India for all their support and love. Finally, I would like to thank my professors from Jadavpur Univeristy in India, who helped me to follow my dream and pursue my doctoral studies at Virginia Tech. Sonal Mazumder Blacksburg, Virginia-USA vi June, 2013 Attribution Professor Richey M. Davis is my research advisor and committee chair. He provided guidance, help, and support throughout the work in this PhD dissertation. Also he significantly contributed to the written communication of the research. Ms. Samantha Casterlow executed the cell toxicity and MIC experiments with the nanoparticles (Chapter 3). Ms. Junia Pereira provided training with HPLC technique and learn about drug release studies from particles. She prepared the CMCAB drug microparticles (Chapter 4). She also synthesized the BPC polymer (Chapter 5). Mr. Haoyu Liu synthesized the cellulose adipates and sebacate, discussed in Chapter 5. He also prepared microparticles with the adipates for the same study. Dr. Bruce Orler helped with the Differential Calorimetry Scans and also provided guidance and reasoning to the results obtained (Chapter 4 and Chapter 5). Mr. Rick Caudill helped with the XRD measurements (Chapter 3, 4 and 5) Ms. Hale Cigdem Arca prepared microparticles and executed dissolution experiments, discussed in Chapter 3. vii TABLE OF CONTENTS Chapter 1: Introduction ________________________________________ 1 1.1. Significance and Motivation ________________________________ 1 1.2. Specific Research Objectives _______________________________ 3 1.3. Overview of Chapters _____________________________________ 6 1.4. References ______________________________________________ 8 Chapter 2: Literature Review ___________________________________ 12 2.1. Introduction to
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