List of Contributors xiii Series Preface xvii List of Abbreviations xix 1 Selecting a Particle Sizer for the Pharmaceutical Industry 1Margarida Figueiredo, M. José Moura and Paulo J. Ferreira 1.1 Introduction 1 1.1.1 Relevance of Particle Size in the Pharmaceutical Industry 1 1.1.2 Main Goals 2 1.1.3 Why it is So Difficult to Select a Particle Sizer 2 1.2 Particle Size Distribution 3 1.2.1 Equivalent Diameter 3 1.2.2 Reporting Particle Size 5 1.2.3 Distribution Statistics 7 1.3 Selecting a Particle Sizer 8 1.3.1 Classification 8 1.3.2 Selection Criteria 9 1.4 Aspects of Some Selected Methods 13 1.4.1 Optical Microscopy-based Methods 13 1.4.2 Laser Light-scattering Techniques 15 1.4.2.1 Laser Diffraction and Static Light Scattering 16 1.4.2.2 Dynamic Light Scattering 19 1.4.3 The Time-of-Flight Counter 20 1.4.4 Cascade Impactor 21 1.5 Conclusions 22 Acknowledgements 22 References 23 2 Spectroscopic Methods in Solid-state Characterization 27Clare Strachan, Jukka Saarinen, Tiina Lipiäinen, Elina Vuorimaa-Laukkanen, Kaisa Rautaniemi, Timo Laaksonen, Marcin Skotnicki and Martin Dračínský 2.1 Solid-state Structure of Particulates 27 2.2 Spectroscopy Overview 28 2.3 Spectroscopic Data Analysis 30 2.3.1 Band Assignment 30 2.3.2 Statistical Analysis 30 2.4 Infrared Spectroscopy 35 2.4.1 Principle 35 2.4.2 MIR Applications 37 2.4.3 MIR Imaging 40 2.5 Near-infrared Spectroscopy 40 2.5.1 Principle 40 2.5.2 NIR Applications 41 2.5.3 NIR Imaging 45 2.6 Terahertz Spectroscopy 46 2.6.1 Principle 46 2.6.2 Terahertz Applications 48 2.6.3 Terahertz Imaging 50 2.7 Raman Spectroscopy 50 2.7.1 Principle 50 2.7.2 Raman Applications 53 2.7.3 Raman Imaging 57 2.8 Nonlinear Optics 59 2.8.1 Principle 59 2.8.2 Nonlinear Optics Applications 61 2.8.3 Nonlinear Optical Imaging 61 2.9 Fluorescence Spectroscopy 65 2.9.1 Principle 65 2.9.2 Fluorescence from Solid-state Samples 67 2.9.3 Intrinsic Fluorophores in Solid Samples 68 2.9.4 Fluorescence Imaging 69 2.9.5 Fluorescence Lifetime Imaging Microscopy 70 2.10 Solid-state Nuclear Magnetic Resonance 71 2.10.1 The Basic Theory of NMR Spectroscopy 71 2.10.2 Solid-state NMR Technique 72 2.10.2.1 Dipole–Dipole Interactions 72 2.10.2.2 Chemical Shift Anisotropy 72 2.10.2.3 Quadrupolar Coupling 73 2.10.2.4 Indirect Coupling 73 2.10.2.5 Magic-angle Spinning and High-power Proton Decoupling 73 2.10.3 Solid-state NMR Experiments 75 2.10.3.1 Sample Preparation 75 2.10.3.2 Cross-polarization 76 2.10.3.3 Heteronuclear Correlation Experiments 77 2.10.4 Pharmaceutical Applications of Solid-state NMR 77 2.11 Conclusions 82 References 84 3 Microfluidic Analysis Techniques for Safety Assessment of Pharmaceutical Nano- and Microsystems 97Tiina M. Sikanen, Iiro Kiiski and Elisa Ollikainen 3.1 Microfluidic Bioanalytical Platforms 97 3.2 Microfabrication Methods and Materials 98 3.3 Microfluidic Cell Cultures 101 3.3.1 Selection of the Microfabrication Material by Design 102 3.3.2 Additional Design Considerations 104 3.3.3 Characterization of Pharmaceutical Nano- and Microsystems Using Organ-on-a-chip 108 3.4 Immobilized Enzyme Microreactors for Hepatic Safety Assessment 109 3.4.1 Nanoparticle Impacts on the Hepatic Clearance of Xenobiotics 109 3.4.2 Cytochrome P450 Interaction Studies in Through-flow Conditions 112 3.4.2.1 Immobilization Strategies for Cytochrome P450 Enzymes 113 3.4.2.2 Microfabrication Materials and Design Considerations 116 3.5 Microfluidic Total Analysis Systems 120 3.5.1 Microfluidic Separation Systems 121 3.5.2 Toward n-in-one Analytical Platforms 124 3.6 Epilogue 126 References 126 4 In Vitro–In Vivo Correlation for Pharmaceutical Nano- and Microsystems 137Preshita P. Desai and Vandana B. Patravale 4.1 Introduction 137 4.2 In Vitro Dissolution and In Vivo Pharmacokinetics 138 4.3 Levels of Correlation 143 4.3.1 Level A Correlation 143 4.3.2 Level B Correlation 144 4.3.3 Level C Correlation 145 4.3.4 Multiple Level C Correlation 145 4.3.5 Level D Correlation 145 4.4 Models of IVIVC 145 4.4.1 Deconvolution Model 146 4.4.2 Convolution Model 149 4.4.3 Miscellaneous Models 149 4.5 IVIVC Model Validation: Predictability Evaluation 150 4.6 IVIVC Development Step-by-Step Approach 151 4.7 Brief Introduction to Micro/Nanosystems and IVIVC Relevance 152 4.7.1 Selection of Appropriate Dissolution Method 153 4.7.2 Selection of Appropriate Dissolution Medium 155 4.7.3 Selection of Appropriate IVIVC Mathematical Model 157 4.8 Applications of IVIVC for Micro/nanoformulations 158 4.8.1 Formulation Optimization 162 4.8.2 Surrogate for Bioequivalence Studies and Biowaivers 165 4.9 Softwares Used for IVIVC 165 4.10 Conclusion and Future Prospects 166 References 166 5 Characterization of Bioadhesion, Mucin-interactions and Mucosal Permeability of Pharmaceutical Nano- and Microsystems 171Ellen Hagesaether, Malgorzata Iwona Adamczak, Marianne Hiorth and Ingunn Tho 5.1 Introduction 171 5.2 Background and Theory 172 5.3 Mucosal Membranes 174 5.3.1 Oral Mucosa 174 5.3.2 Gastrointestinal Mucosa 176 5.3.3 Pulmonary Mucosa 176 5.3.4 Nasal Mucosa 181 5.3.5 Ocular Mucosa 182 5.3.6 Vaginal Mucosa 182 5.4 Use of Mucosal Membranes in Studies of Micro- and Nanoparticles 183 5.4.1 Diffusion Chambers 183 5.4.2 Permeability Support for Cell-based Systems 184 5.5 Selection of Biological Models 185 5.5.1 Tissue-based Models 185 5.5.2 Cell-based Models 185 5.5.3 Mucus as Models 187 5.5.4 Artificial Models 188 5.6 Methods for Testing Biocompatibility 189 5.6.1 Viability 189 5.6.2 Cytotoxicity 189 5.6.3 Paracellular Permeability 189 5.7 Methods for Testing Mucoadhesion 190 5.7.1 Atomic Force Microscopy (AFM) 190 5.7.2 Quartz Crystal Microbalance (QCM) 191 5.7.3 Rheology 192 5.7.4 Rheology in Combination with Light Scattering (Rheo-SALS) 192 5.7.5 Dynamic Light Scattering (DLS) and Zeta Potential Measurements 193 5.7.6 Mechanical Methods 194 5.7.7 Mucin Adsorption Study 194 5.7.8 Wash-off Tests 194 5.8 Methods for Testing Mucopenetration 195 5.8.1 Fluorescent Recovery after Photobleaching (FRAP) and Multiple Image Photography (MIP) 195 5.8.2 Permeability Studies 195 5.8.3 Water-assisted Transport Through Mucus 196 5.8.4 Particles with Dynamic Properties 196 5.9 Methods for Assessing Cell Interactions 197 5.9.1 Cell Adhesion 197 5.9.2 Cellular Uptake 197 5.9.3 Transcellular Transport 199 5.10 Concluding Remarks 203 References 203 6 Cell–Nanoparticle Interactions: Toxicity and Safety Issues 207Flavia Fontana, Nazanin Zanjanizadeh Ezazi, Nayab Tahir and Helder A. Santos 6.1 Introduction 207 6.1.1 Role of Nanoparticles in Modern Medicine and Applications 207 6.1.2 Cell–NP Interactions 208 6.1.2.1 Size 208 6.1.2.2 Shape 208 6.1.2.3 Surface Charge 209 6.1.2.4 Surface Functionalization and Hydrophobicity 210 6.1.2.5 Protein Corona 211 6.1.3 NP Toxicity 211 6.2 Mechanisms of NP-Induced Cellular Toxicity 211 6.2.1 Damage to the Plasma Membrane 211 6.2.2 Alterations or Disruptions in the Cytoskeleton 211 6.2.3 Mitochondrial Toxicity 216 6.2.4 Nuclear Damage 216 6.2.5 Reactive Oxygen Species (ROS) 216 6.2.6 Interference in the Signaling Pathways 216 6.3 In Vitro Assays to Evaluate Cell–NP Interactions 216 6.3.1 Traditional Assays 217 6.3.2 Innovative Assays 217 6.4 Metal Oxide Nanoparticles 217 6.4.1 Zinc Oxide 217 6.4.2 Cerium Oxide 220 6.4.3 Iron Oxide 221 6.5 Non-metallic Nanoparticles 223 6.5.1 Liposomes 223 6.5.2 Polymeric Delivery Systems 224 6.5.3 Dendrimers 230 6.5.4 Silicon/Silica-based Drug Delivery Systems 232 6.6 Conclusions and Future Perspectives 235 Acknowledgements 235 References 236 7 Intestinal Mucosal Models to Validate Functionalized Nanosystems 243Cláudia Azevedo, Inês Pereira and Bruno Sarmento 7.1 Introduction 243 7.2 Intestinal Mucosal Characteristics 244 7.2.1 Intestinal Morphology 244 7.2.2 Transport Mechanisms 246 7.3 In Vitro Models 248 7.3.1 Monoculture Models 249 7.3.2 Co-culture Models 252 7.3.2.1 The Caco-2/HT29-MTX Model 252 7.3.2.2 The Caco-2/Raji B Model 253 7.3.2.3 The Caco-2/HT29-MTX/Raji B Model 253 7.3.3 3D Co-culture Models 253 7.3.4 Gut-on-a-Chip 254 7.4 Ex Vivo Intestinal Models for In Vitro/In Vivo Correlation of Functionalized Nanosystems 258 7.4.1 Diffusion Chambers 258 7.4.1.1 Ussing Chamber 258 7.4.1.2 Franz Cell 258 7.4.2 Everted Intestinal Sac Model 259 7.4.3 Non-everted Intestinal Sac Model 260 7.4.4 Everted Intestinal Ring 260 7.5 In Situ Models 260 7.5.1 Intestinal Perfusion 262 7.5.2 Intestinal Loop 264 7.5.3 Intestinal Vascular Cannulation 264 7.6 In Vivo Models 264 7.7 Conclusion 265 Acknowledgements 266 References 267 8 Biodistribution of Polymeric, Polysaccharide and Metallic Nanoparticles 275Nazl𝚤 Erdoğar, Gamze Varan, Cem Varan and Erem Bilensoy 8.1 Introduction 275 8.2 Biodistribution and Pharmacokinetics 276 8.3 Mechanisms Affecting Biodistribution 277 8.3.1 Nanoparticle Properties 277 8.3.1.1 Effect of Particle Size 277 8.3.1.2 Effect of Surface Charge 279 8.3.1.3 Effect of Particle Shape 280 8.3.2 Dosing and Toxicity 281 8.3.3 Effect of Coating 282 8.4 Conclusion 285 References 286 9 Opportunities and Challenges of Silicon-based Nanoparticles for Drug Delivery and Imaging 291Didem Şen Karaman, Martti Kaasalainen, Helene Kettiger and Jessica M. Rosenholm 9.1 Synthesis and Characteristics of Silica-based Nanoparticles 292 9.1.1 Nonporous Silica NPs 292 9.1.2 Mesoporous Silica NPs 295 9.1.3 Core@Shell Materials 297 9.1.4 Hollow Silica Nanoparticles 298 9.1.5 Porous Silicon (PSi) 300 9.2 Solid-state Characterization 303 9.2.1 Porosity and Morphology on the Nanoscale 303 9.2.2 Structural Analysis 305 9.2.3 Methods for Determination of Surface Functionalization 306 9.3 Medium-dependent Characterization 307 9.3.1 Hydrodynamic Size 307 9.3.1.1 Dynamic Light Scattering 309 9.3.2 Surface Charge and Zeta Potential 309 9.3.3 Colloidal Stability 311 9.3.4 Challenges in Particularly Porous Nanoparticle Characterization 312 9.4 Incorporation of Active Molecules 314 9.4.1 Drug Loading 314 9.4.2 Labeling with Imaging Agents 317 9.5 Biorelevant Physicochemical Characterization 319 9.5.1 Biodegradation/Dissolution of Silica 321 9.5.2 Biocompatibility and Nano–Bio Interactions 323 9.5.3 Drug Release 324 9.5.4 Label-free (Imaging) Technologies 326 9.6 Conclusions 328 References 329 10 Statistical Analysis and Multidimensional Modeling in Research 339Osmo Antikainen 10.1 Measurement in Research 339 10.2 Mean and Sample Mean 339 10.3 Correlation 341 10.4 Modeling Relationships Between Series of Observations 343 10.5 Quality of a Model 344 10.5.1 The Meaning of R2 in Linear Regression 344 10.5.2 Cross-validation 345 10.6 Multivariate Data 350 10.6.1 Screening Designs 351 10.6.2 Full Factorial Designs 352 10.6.2.1 Full Factorial Designs in Two Levels 352 10.6.2.2 Full Factorial Designs in Three Levels (3n Design) 355 10.7 Principal Component Analysis (PCA) 362 10.8 Conclusions 366 References 366 Index 369

Characterization of Pharmaceutical Nano- and Microsystems Learn about the analytical tools used to characterize particulate drug delivery systems with this comprehensive overview Edited by a leading expert in the field, Characterization of Pharmaceutical Nano- and Microsystems provides a complete description of the analytical techniques used to characterize particulate drug systems on the micro- and nanoscale. The book offers readers a full understanding of the basic physicochemical characteristics, material properties and differences between micro- and nanosystems. It explains how and why greater experience and more reliable measurement techniques are required as particle size shrinks, and the measured phenomena grow weaker. Characterization of Pharmaceutical Nano- and Microsystems deals with a wide variety of topics relevant to chemical and solid-state analysis of drug delivery systems, including drug release, permeation, cell interaction, and safety. It is a complete resource for those interested in the development and manufacture of new medicines, the drug development process, and the translation of those drugs into life-enriching and lifesaving medicines. Characterization of Pharmaceutical Nano- and Microsystems covers all of the following topics: An introduction to the analytical tools applied to determine particle size, morphology, and shapeCommon chemical approaches to drug system characterizationA description of solid-state characterization of drug systemsDrug release and permeation studiesToxicity and safety issuesThe interaction of drug particles with cells Perfect for pharmaceutical chemists and engineers, as well as all other industry professionals and researchers who deal with drug delivery systems on a regular basis, Characterization of Pharmaceutical Nano- and Microsystems also belongs on bookshelves of interested students and faculty who interact with this topic.