The intestine, particularly the small bowel, represents a large surface (in the adult 2 human approximately 200 m ) through which the body is exposed to its environ ment. A vigorous substrate exchange takes place across this large surface: nutrients and xenobiotics are absorbed from the lumen into the bloodstream or the lymph, and simultaneously, the same types of substrate pass back into the lumen. The luminal surface of the intestine is lined with a "leaky" epithelium, thus the passage of the substrates, in either direction, proceeds via both transcellular and intercellular routes. Simple and carrier-mediated diffusion, active transport, pinocytosis, phagocytosis and persorption are all involved in this passage across the intestinal wall. The term "intestinal permeation" refers to the process of passage of various substances across the gut wall, either from the lumen into the blood or lymph, or in the opposite direction. "Permeability" is the condition of the gut which governs the rate of this complex two-way passage. The pharmacologist's interest in the problem of intestinal permeation is twofold: on the one hand, this process determines the bioavailability of drugs and contributes significantly to the pharmacokinetics and toxicokinetics of xeno biotics; on the other hand, the pharmacodynamic effects of many drugs are manifested in a signigicant alteration of the physiological process of intestinal permeation.

The intestine, particularly the small bowel, represents a large surface (in the adult 2 human approximately 200m ) through which the body is exposed to its environment. A vigorous substrate exchange takes place across this large surface: nutrients and xenobiotics are absorbed from the lumen into the bloodstream or the lymph, and simultaneously, the same types of substrate pass back into the lumen. The luminal surface of the intestine is lined with a "leaky" epithelium, thus the passage of the substrates, in either direction, proceeds via both transcellular and intercellular routes. Simple and carrier-mediated diffusion, active transport, pinocytosis, phagocytosis and persorption are all involved in this passage across the intestinal wall. The term "intestinal permeation" refers to the process of passage of various substances across the gut wall, either from the lumen into the blood or lymph, or in the opposite direction. "Permeability" is the condition of the gut which governs the rate of this complex two-way passage. The pharmacologist's interest in the problem of intestinal permeation is twofold: on the one hand, this process determines thebioavailability of drugs and contributes significantly to the pharmacokinetics and toxicokinetics of xeno biotics; on the other hand, the pharmacodynamic effects of many drugs are manifested in a significant alteration of the physiological process of intestinal permeation.

Oral Drug Absorption, Second Edition thoroughly examines the special equipment and methods used to test whether drugs are released adequately when administered orally. The contributors discuss methods for accurately establishing and validating in vitro/in vivo correlations for both MR and IR formulations, as well as alternative approaches for MR an

“Infogest” (Improving Health Properties of Food by Sharing our Knowledge on the Digestive Process) is an EU COST action/network in the domain of Food and Agriculture that will last for 4 years from April 4, 2011. Infogest aims at building an open international network of institutes undertaking multidisciplinary basic research on food digestion gathering scientists from different origins (food scientists, gut physiologists, nutritionists...). The network gathers 70 partners from academia, corresponding to a total of 29 countries. The three main scientific goals are: Identify the beneficial food components released in the gut during digestion; Support the effect of beneficial food components on human health; Promote harmonization of currently used digestion models Infogest meetings highlighted the need for a publication that would provide researchers with an insight into the advantages and disadvantages associated with the use of respective in vitro and ex vivo assays to evaluate the effects of foods and food bioactives on health. Such assays are particularly important in situations where a large number of foods/bioactives need to be screened rapidly and in a cost effective manner in order to ultimately identify lead foods/bioactives that can be the subject of in vivo assays. The book is an asset to researchers wishing to study the health benefits of their foods and food bioactives of interest and highlights which in vitro/ex vivo assays are of greatest relevance to their goals, what sort of outputs/data can be generated and, as noted above, highlight the strengths and weaknesses of the various assays. It is also an important resource for undergraduate students in the ‘food and health’ arena.

This book intends to be an updated compilation of the most important buccal, gastric, intestinal, pulmonary, nasal, vaginal, ocular, skin and blood-brain barrier in vitro models for predicting the permeability of drugs. Concepts and Models for Drug Permeability Studies focuses on different approaches and comprises of various models. Each model describes the protocol of seeding and conservation, the application for specific drugs, and takes into account the maintenance of physiologic characteristics and functionality of epithelium, from the simplest immortalized cell-based monoculture to the most complex engineered-tissue models. Chapters also discuss the equivalence between in vitro cell and tissue models and in vivo conditions, highlighting how each model may provisionally resemble a different drug absorption route. - Updated information regarding the most recent in vitro models to study the permeability of drugs - Short and concise chapters covering all the biological barriers with interest in drug permeability - A combination of bibliographic information related with individual models and footnote instructions of technical procedures for construction of cell and tissue-based models - Simple and clear scientific content, adaptable for young scientists and experimented researchers

This is a well thought-out, highly practical text covering contemporary ‘in vitro’ techniques for drug absorption studies. Starting at the molecular level of investigation, it continues with cell monolayer models (both primary and cell lines) and culminates with in situ techniques as a final testing format. In addition, chapters on high-throughput assays, in vitro-in vivo correlation, bioinformatics and regulatory issues are covered, giving a comprehensive overview of available models and techniques. Moreover, an appendix consisting of a number of practical protocols is available online, updated as needed, and should prove very helpful to apply the techniques directly to the benchside.

Thirteen chapters by industrial and academic authorities in this rapidly evolving field present detailed case histories and reviews of current sophisticated protein-drug delivery technologies. Highlights include a comprehensive overview of insulin delivery and a discussion of the use of biodegradable microspheres.

ORAL BIOAVAILABILITY AND DRUG DELIVERY Improve the performance and viability of newly-developed and approved drugs with this crucial guide Bioavailability is the parameter which measures the rate and extent to which a drug reaches a user’s circulatory system depending on the method of administration. For example, intravenous administration produces a bioavailability of 100%, since the drugs are injected directly into the circulatory system; in the case of oral administration, however, bioavailability can vary widely based on factors which, if not properly understood, can result in a failure in drug development, adverse effects, and other complications. The mechanics of oral bioavailability are therefore critical aspects of drug development. Oral Bioavailability and Drug Delivery provides a comprehensive coverage of this subject as well as its drug development applications. Beginning with basic terminology and fundamental concepts, it provides a thorough understanding of the challenges and barriers to oral bioavailability as well as the possibilities for improving this parameter. The resulting book is an indispensable tool for drug development research. Oral Bioavailability and Drug Delivery readers will also find: Discussion questions in many chapters to facilitate comprehension Detailed discussion of topics including dissolution, absorption, metabolism, and more Real-world examples of methods in actions throughout Oral Bioavailability and Drug Delivery is ideal for pharmaceutical and biotechnology scientists working in drug discovery and development; researchers in chemistry, biology, pharmacology, immunology, neuroscience, and other related fields; and graduate courses in drug development and delivery.

This book gives the reader an introduction to the field of surfactants in solution as well as polymers in solution. Starting with an introduction to surfactants the book then discusses their environmental and health aspects. Chapter 3 looks at fundamental forces in surface and colloid chemistry. Chapter 4 covers self-assembly and 5 phase diagrams. Chapter 6 reviews advanced self-assembly while chapter 7 looks at complex behaviour. Chapters 8 to 10 cover polymer adsorption at solid surfaces, polymers in solution and surface active polymers, respectively. Chapters 11 and 12 discuss adsorption and surface and interfacial tension, while Chapters 13- 16 deal with mixed surfactant systems. Chapter 17, 18 and 19 address microemulsions, colloidal stability and the rheology of polymer and surfactant solutions. Wetting and wetting agents, hydrophobization and hydrophobizing agents, solid dispersions, surfactant assemblies, foaming, emulsions and emulsifiers and microemulsions for soil and oil removal complete the coverage in chapters 20-25.