Preface

Scientists who dedicate their research activity to biomaterials pass through the typical dichotomy that often characterizes the basic researc. On one side is the wish of exploring new frontiers of chemistry, physics, biology, medicine, pharmaceutics and all other disciplines to which biomaterials can be applied. The constantly improving scientific knowledge would feed the freedom of attempting new strategies for producing materials with always tailored and improved characteristics. On the other side, one should one have a look to the different 'official' definitions given for biomaterials. It is evident how the restriction imposed by words would limit the fantasy and effectiveness of fundamental scientific research. Just as an examplebiomaterials are defined as a 'nonviable material used in a medical device, intended to interact with biological systems ' (Consensus Conference of the European Society for Biomaterials, 1986), or as 'any substance (other than a drug) or combination of substances, synthetic or natural in origin, which can be used (…) as a whole or as a part of a system which treats, augments, or replaces any tissue, organ, or function of the body (NIH), or even 'a systematically and pharmacologically inert substance designed for implantation within or incorporation with living systems' (Clemson University Advisory Board for Biomaterials). Essentially, the only common property is that a biomaterial would be different from a biological material, that is produced by a biological system. Clearly, none of the proposed definitions can succeed to cover the whole landscape of properties and applications of these peculiar compounds, but they can only enlighten a particular aspect of their potentials. A similar situation can be applied for nanomedicine – a research field with which the field of biomaterials actually often shares technologies and applications – and for which is the gap between 'official' definitions and the originality of published researches even larger.

These considerations have been one of the basis of the present editorial task, that will comprehend three volumes focused on the recent developments and applications of biomaterials. These books collect review articles, original researches and experimental reports from eminent experts from all over the word, who have been working in this scientific area for a long time. The chapters are covering the interdisciplinary arena which is necessary for an effective development and usage of biomaterials. Contributors were asked to give their personal and recent experience on biomaterials, regardless any specific limitation due to fit into one definition or the other. In our opinion, this will give readers a wider idea on the new and ongoing potentials of different synthetic and engineered macromolecular materials.

In the meantime, another editorial guidance was not to force the selection of papers concerning the market or clinical applications or biomaterial products. The aim of the book was to gather all results coming from very fundamental studies. Again, this will allow to gain a more general view of what and how the various biomaterials can do and work for, along with the methodologies necessary to design, develop and characterize them, without the restrictions necessarily imposed by industrial or profit concerns.

The chapters have been arranged to give readers an organized view of this research field. In particular, this book contains 25 chapters related to recent research on new materials, with a particular attention to their physical, mechanical and chemical characterization. The first section of the volume contains 9 reviews and articles focused on chemical and engineering modification of biomaterials for specific applications. The following 10 chapters deal with physical and biomechanical studies on biomaterials, followed by two sections which report some recent studies on the interactions and compatibility of biomaterials with biological media, as well as on the management of the phenomena that can occur at the biomaterial/tissue interfaces, such as biofilm formation.

I am sure that readers will gain an improved understanding of the full range of disciplines and design methodologies that are used to develop biomaterials with the physical and biological properties needed for specific clinical applications.

I hope that you will find all these contributions interesting, and that you will be inspired from their reading to broaden your own research towards the exciting field of biomaterial development and applications.

> **Prof. Rosario Pignatello** Department of Pharmaceutical Sciences Faculty of Pharmacy University of Catania Italy
