A Thesis entitled Nose to Brain Delivery of Antiepileptic Drugs Using Nanoemulsions by Salam Shanta Taher Al-Maliki Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Pharmaceutical Sciences, Industrial Pharmacy ________________________________________ Jerry Nesamony, Ph.D., Committee Chair ________________________________________ Sai Hanuman Sagar Boddu, PhD, Committee Member ________________________________________ Caren L. Steinmiller, PhD, Committee Member ________________________________________ Patricia R. Komuniecki, PhD, Dean College of Graduate Studies The University of Toledo December 2015 Copyright 2015, Salam Al-Maliki This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of Nose to Brain Delivery of Antiepileptic Drugs Using Nanoemulsions by Salam Al-Maliki Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Master of Science Degree in Pharmaceutical Sciences Industrial Pharmacy The University of Toledo December 2015 The objective of this research work was to formulate and develop an intranasal oil-in- water nanoemulsion (NE) using spontaneous emulsification method. Based on ternary phase diagram, emulsification time, and drug solubility study, the composition ratio of surfactant:co-surfactant:oil was optimized to 2:1:1. The model antiepileptic drug chosen for loading was phenytoin. The NE preparation was evaluated for particle size, zeta potential, electrical conductivity, pH, % transmittance, polarized light microscopy, in vitro drug release studies using HPLC, sterility validation, differential scanning calorimetry (DSC), and in vitro nasal toxicity testing in bovine nasal mucosa. The nanoemulsion formulations were then subjected to stability studies for six months by storing formulations at 25±5°C and 5±3°C. The NE exhibited a clear and stable formulation with globule size less than 20 nm and neutral zeta potential. The absence of birefringence and high conductivity values indicated that the formulations were o/w NE. The pH measurements confirmed compatibility of such formulation for intranasal delivery. In vitro release study showed 100% release of the drug from NE over a period iii of 48 hours. The absence of any endothermic events in the phenytoin - self nanoemulsifying mixture (SNE) when analyzed in DSC conclusively indicated that phenytoin was completely solubilized in this mixture.The histopathological studies of optimized formulation did not show signs of damage on the nasal mucosa.The results of the sterility verification test demonstrated that the sterilization of the final formulation using aseptic filtration with 0.22µm filter was sufficient for rendering the formulation aseptic. The nanoemulsion was found to be stable in all the temperature conditions when particle size distribution, drug content, pH, and conductivity were taken as stability indicating parameters during the six-month study period. Based on the obtained results, the o/w phenytoin NE was found to be stable and desirable for use in intra-nasal delivery. iv Dedicated to my family Acknowledgements I would like to express my gratitude to Dr. Jerry Nesamony for providing me an opportunity to be a part of his research group. This work would not have been possible without his valuable advice and excellent support all throughout the two years of graduate study. He provided me with all the resources and guidances that allowed me to succeed in this project. I would like to specially thank Dr. Sai Boddu and Dr. Caren Steinmiller for serving as my committee members. I want to thank Dr. Alexander for all the knowledge gained. I thank Dr.Wissam A. AbouAlaiwi for his help with the polarized light microscopy and for agreeing to be the graduate faculty representative. I also thank thank Dr. Andrea Kalinoski for helping me with the histopathology study. I would also like to thank my sponsorship Higher Committee for Education Development in Iraq (HCED) for supporting me financially throughout my graduate school. I would like to thank my fellow classmate Zahraa Al-Saedi for her support, encouragement and help with my research. Special thanks to all my friends Ahmed Fahad, Rajan, and Rinda who supported me during the research and writing. Finally, I would like to thank my wife and my kids, my parents, my brother, cousins and my entire family, for their unlimited support and encouragement during my studies. v Table of Contents Abstract .............................................................................................................................. iii Acknowledgements ..............................................................................................................v Table of Contents ............................................................................................................... vi List of Tables ..................................................................................................................... ix List of Figures ......................................................................................................................x 1. Introduction ....................................................................................................................1 1.1 Physiology and function of nose ........................................................................2 1.1.1. Breathing ............................................................................................2 1.1.2. Filtration .............................................................................................3 1.1.3. Heating and humidification................................................................4 1.1.4. Olfaction and sensation ......................................................................4 1.1.5. Mucociliary clearance activity ...........................................................6 1.2 Anatomy of the nose ..........................................................................................7 1.2.1. External nose ......................................................................................7 1.2.2. Nasal cavity ........................................................................................7 1.2.2.1 Nasal vestibule .....................................................................8 1.2.2.2 Nasal valve ..........................................................................8 1.2.2.3 The respiratory region .........................................................9 vi 1.2.2.4 Olfactory region .................................................................10 1.2.2.5 Nasopharynx ......................................................................11 1.3.Nasal drug delivery ..........................................................................................12 1.3.1. Local delivery ..................................................................................12 1.3.1.1 Nasal decongestant drugs ...................................................12 1.3.1.2 Intranasal antihistamines and corticosteroid drugs ............13 1.3.1.3 Intranasal topical anesthetic agents ...................................15 1.3.2. Systemic delivery .............................................................................16 1.3.2.1. Analgesic agents (opioid and non-opioid agents) ............17 1.3.2.2. Cardiovascular agents .......................................................20 1.3.2.3. Anti-emetic agents ............................................................21 1.3.2.4. Anti-diabetic agents ..........................................................23 1.3.2.5. IN vaccine .........................................................................25 1.3.3. CNS delivery (direct Nose to brain delivery) .................................27 1.4 Nanostructured for IN drug delivery and brain targeting ...............................30 1.4.1. Microemulsion .................................................................................31 1.4.2. Solid lipid nanoparticles ..................................................................33 1.4.3. liposomes .........................................................................................34 1.4.4.Other colloidal carrier (polymeric micelle,dendrimer and NS) ........36 1.5.Antiepileptic drugs ...........................................................................................38 1.5.1. History..............................................................................................38 1.5.2 Mechanism of action .........................................................................39 1.5.3 Commercially available antiepileptic dosage forms .........................39 vii 1.5.4 Alternative methods for delivery of antiepileptic drug to the brain..43 2. Significance of Research..............................................................................................46 3. Nose to Brain Delivery of Antiepileptic Drugs Using nanoemulsion system .............48 3.1. Abstract ...........................................................................................................48 3.2. Introduction .....................................................................................................49 3.3. Materials and Methods ....................................................................................51 4. Results and Discussion ..........................................................................................62