Man has recognised an association of light with life and medicine for over 3000 years. Today the major challenges to this topic include the elucidation of photochemical reactions involved in photobiology at the molecular level. This includes the use of a variety of modem probing techniques that directly measures the reactivity of excited states and free radicals involved in biological reactions. This text-book is based on such an approach and has arisen from some of the lectures delivered at the NATO ASI held at Hotel Capo Caccia near the Centre for Advanced Research in Photobiology (CARP) in Sardegia, Italy. The ASI took place from 30 September -13 October 1993 and involved a total membership of 90. The book, like the NATO ASI itself, is divided into four themes starting with fundamental aspects and ending with complex medically related systems. Thus Theme 1 covers aspects of the underlying photophysics and photochemistry with particular emphasis on modem experimental techniques to study molecular mechanisms of biological processes. Theme 2 applies many of these fundamental studies to the chemical reactions of most relevance to photobiology and photomedicine such as photo-addition, -isomerization, -sensitization and -pigmentation. The third and fourth Themes deal with the deleterious and therapeutic aspects of light with particular emphasis on the use of Photo-Dynamic Therapy (PDT) to treat cancer and on viral and micro bioi infections.

Radiation induces a variety of chemical processes in biological tissues. This volume is a synthesis of up-to-the-minute reviews on such photochemical and photobiological sensitized reactions with particular relevance to photomedicine. The first part gives a description of experimental techniques for the study of the primary processes after radiation absorption by biological systems. It is followed by chapters on singlet oxygen and photomedicine, considering both phototherapy and photochemotherapy. These sections also discuss the next generation of potential photosensitizing drugs.

Man has recognised an association of light with life and medicine for over 3000 years. Today the major challenges to this topic include the elucidation of photochemical reactions involved in photobiology at the molecular level. This includes the use of a variety of modem probing techniques that directly measures the reactivity of excited states and free radicals involved in biological reactions. This text-book is based on such an approach and has arisen from some of the lectures delivered at the NATO ASI held at Hotel Capo Caccia near the Centre for Advanced Research in Photobiology (CARP) in Sardegia, Italy. The ASI took place from 30 September -13 October 1993 and involved a total membership of 90. The book, like the NATO ASI itself, is divided into four themes starting with fundamental aspects and ending with complex medically related systems. Thus Theme 1 covers aspects of the underlying photophysics and photochemistry with particular emphasis on modem experimental techniques to study molecular mechanisms of biological processes. Theme 2 applies many of these fundamental studies to the chemical reactions of most relevance to photobiology and photomedicine such as photo-addition, -isomerization, -sensitization and -pigmentation. The third and fourth Themes deal with the deleterious and therapeutic aspects of light with particular emphasis on the use of Photo-Dynamic Therapy (PDT) to treat cancer and on viral and micro bioi infections.

The fIrst edition of the Science 0/ Photobiology edited by Kendric C. Smith (plenum Press, 1977) was a comprehensive textbook of photobiology, devoting a chapter to each of the subdisciplines of the fIeld. At the end of many of these chapters there were brief descriptions of simple experiments that students could perform to demonstrate the principles discussed. In the succeeding years some photobiologists felt that a more complete publica tion of experiments in photobiology would be a useful teaching tool. Thus, in the 1980s the American Society for Photobiology (ASP) attempted to produce a laboratory manual in photobiology. Cognizant of these efforts, Kendric Smith elected to publish the second edition of The Science o/Photobiology (1989) without experiments; anticipating the comple tion of the ASP laboratory manual. Unfortunately, the initial ASP efforts met with limited success, and several years were to pass before a photobiology laboratory manual became a reality. One of the major stumbling blocks to production of an accurate and reliable laboratory manual was the requirement that the experiments be tested, not just by the author who is familiar with the techniques, but by students who may be quite new to photobiology. How could this be accomplished with limited resources? Many ideas were considered and discarded, before a workable solution was found. The catalyst that enabled the careful screening of all experiments in this book was a NATO Advanced Study Institute (ASI) devoted entirely to this purpose."