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Bioactive polymeric systems, an overview
89
butions by European and Japanese workers. The Introduction by F. Cramer is mainly a personal reminiscence. Chapter 1 (G. Tsoucaris) is a review with 74 references of the structures of clathrates; alone among the chapters in the book this one has not,hing specifically to do with the cyclodextrins. The next chapter, by P.J. Sicard and M-H. Saniez, is a useful treatment (57 references) of microorganisms containing cycloglycosyltransferase, with enzyme properties, and processes for the isolation and purification of cyclodextrins. In Chapter 3 D. Le Bas and N. Rysanek present a well-illustrated review of crystal structure data on cyclodextrins and their complexes (55 references) . Their structural viewpoint perhaps leads them to an oversimplified picture of the binding energetics in aqueous solution. Chapter 4 (F. Hirayama and K. Uekama) discusses physical methods for detecting complexes and gives descriptions of the solubility, kinetic, potentiometric, and chromatographic methods for determining binding constants (133 references). Some thermodynamic data are given, and the preparation of solid-state complexes is described. J. Szejtli in Chapter 5 provides a valuable review of the metabolism and toxicology of cyclodextrins (69 references). Cyclodextrins are completely resistant top-amylases because they have no end groups, but they are slowly degraded by oc-amylases. Metabolism in animals occurs mainly in the colon. Cyclodextrins appear to be non-toxic orally, but cause nephrosis when injected in large doses. Duchene, Glomot, and Vaution (Chapter 6, 100 references) review the literature of pharmaceutical applications (most of them potential rather than actual 1, which include effects on drug stability, solubility, dissolution rate, bioavailability, and pharmacokinetics. The chromatographic applications of cyclodextrins are treated by E. Smolkova-Keulemansova (Chapter 7, 88 references) . Cyclodextrins are especially interesting in the form of chemically bonded stationary phases for liquid chromatography, and as chiral phases; they have also been used for gas chro-
matography. Incorporation of cyclodextrins in mobile liquid phases provides a secondary equilibrium for resolutions. In Chapter 8 (244 references, mostly patents) C. Vaution, M. Hutin, F. Glomot, and D. Duchene describe uses that have been suggested in several industries, particularly in cosmetics and foods. Stabilization of active ingredients and improved physical properties of cosmetic substances and formulations are the usual goals, but other advantages of the cyclodextrins have been claimed, for example for odor reduction, decreased skin irritation, and even as an active ingredient against acne. In the food field, stabilization is the leading application, with other improvements being claimed in flavors and aromas, lessened bitterness, and improved materials handling. Chapter 9 is a very useful review by B. Sebille, with 124 references, of covalently modified cyclodextrins, including their polymers. In Chapter 10 K. Uekama and T. Irie discuss pharmaceutical applications of methylated cyclodextrins, of which the most studied is heptakis- ( 2,6-di-O-methyl) P-cyclodextrin (often misleadingly called dimethyl p-cyclodextrin in the literature). The methylated cyclodextrins have higher solubilities than the native cyclodextrins, and they possess surfactant properties. Their chemistry, toxicology, and pharmaceutics are discussed. Although some of these chapters cover wellreviewed areas, others constitute valuable new resources of previously scattered information. This book would be a useful acquisition for any laboratory planning to investigate applications of the cyclodextrins. KENNETHA.CONNORS Llniversity of Wisconsin-Madison
C.G. Gebelein and C.E. Carraher, Polymeric
Systems,
An
Jr., Bioactiue Plenum 1985, vii + 689
Overview,
Press, New York and London, pages, $95.00 (U.S.A. ) .
Many books have been published over the last years in the field of bioactive polymeric sys-
90
terns. This book reviews a wide variety of such systems, and is written by experts in their fields for scientists who are not experts in this area. It provides useful information of how a specialist might attack a problem. The 22 chapters contain an aggregated total of about 3000 references and will enable the reader to obtain a further background. The organization of this book is the following: chapter 1: Overview; chapters 2-8: Controlled-Release Systems; chapters 9 and 10: Special Experimental Techniques; chapters 11-15: Natural Polymer Systems; chapters 16 and 17: Pseudonatural Polymer Systems; chapters 18-22:
Synthetic Polymer Systems. At the end, the reader will find an extensive and useful subject index. The objective of the editors was to emphasize a multidisciplinary approach, and also to encourage the reader to consider the use of new techniques. This book is an excellent overview of the field and is a recommended addition to the researcher’s library.
RGURNY IJniuersity
of Geneva
butions by European and Japanese workers. The Introduction by F. Cramer is mainly a personal reminiscence. Chapter 1 (G. Tsoucaris) is a review with 74 references of the structures of clathrates; alone among the chapters in the book this one has not,hing specifically to do with the cyclodextrins. The next chapter, by P.J. Sicard and M-H. Saniez, is a useful treatment (57 references) of microorganisms containing cycloglycosyltransferase, with enzyme properties, and processes for the isolation and purification of cyclodextrins. In Chapter 3 D. Le Bas and N. Rysanek present a well-illustrated review of crystal structure data on cyclodextrins and their complexes (55 references) . Their structural viewpoint perhaps leads them to an oversimplified picture of the binding energetics in aqueous solution. Chapter 4 (F. Hirayama and K. Uekama) discusses physical methods for detecting complexes and gives descriptions of the solubility, kinetic, potentiometric, and chromatographic methods for determining binding constants (133 references). Some thermodynamic data are given, and the preparation of solid-state complexes is described. J. Szejtli in Chapter 5 provides a valuable review of the metabolism and toxicology of cyclodextrins (69 references). Cyclodextrins are completely resistant top-amylases because they have no end groups, but they are slowly degraded by oc-amylases. Metabolism in animals occurs mainly in the colon. Cyclodextrins appear to be non-toxic orally, but cause nephrosis when injected in large doses. Duchene, Glomot, and Vaution (Chapter 6, 100 references) review the literature of pharmaceutical applications (most of them potential rather than actual 1, which include effects on drug stability, solubility, dissolution rate, bioavailability, and pharmacokinetics. The chromatographic applications of cyclodextrins are treated by E. Smolkova-Keulemansova (Chapter 7, 88 references) . Cyclodextrins are especially interesting in the form of chemically bonded stationary phases for liquid chromatography, and as chiral phases; they have also been used for gas chro-
matography. Incorporation of cyclodextrins in mobile liquid phases provides a secondary equilibrium for resolutions. In Chapter 8 (244 references, mostly patents) C. Vaution, M. Hutin, F. Glomot, and D. Duchene describe uses that have been suggested in several industries, particularly in cosmetics and foods. Stabilization of active ingredients and improved physical properties of cosmetic substances and formulations are the usual goals, but other advantages of the cyclodextrins have been claimed, for example for odor reduction, decreased skin irritation, and even as an active ingredient against acne. In the food field, stabilization is the leading application, with other improvements being claimed in flavors and aromas, lessened bitterness, and improved materials handling. Chapter 9 is a very useful review by B. Sebille, with 124 references, of covalently modified cyclodextrins, including their polymers. In Chapter 10 K. Uekama and T. Irie discuss pharmaceutical applications of methylated cyclodextrins, of which the most studied is heptakis- ( 2,6-di-O-methyl) P-cyclodextrin (often misleadingly called dimethyl p-cyclodextrin in the literature). The methylated cyclodextrins have higher solubilities than the native cyclodextrins, and they possess surfactant properties. Their chemistry, toxicology, and pharmaceutics are discussed. Although some of these chapters cover wellreviewed areas, others constitute valuable new resources of previously scattered information. This book would be a useful acquisition for any laboratory planning to investigate applications of the cyclodextrins. KENNETHA.CONNORS Llniversity of Wisconsin-Madison
C.G. Gebelein and C.E. Carraher, Polymeric
Systems,
An
Jr., Bioactiue Plenum 1985, vii + 689
Overview,
Press, New York and London, pages, $95.00 (U.S.A. ) .
Many books have been published over the last years in the field of bioactive polymeric sys-
90
terns. This book reviews a wide variety of such systems, and is written by experts in their fields for scientists who are not experts in this area. It provides useful information of how a specialist might attack a problem. The 22 chapters contain an aggregated total of about 3000 references and will enable the reader to obtain a further background. The organization of this book is the following: chapter 1: Overview; chapters 2-8: Controlled-Release Systems; chapters 9 and 10: Special Experimental Techniques; chapters 11-15: Natural Polymer Systems; chapters 16 and 17: Pseudonatural Polymer Systems; chapters 18-22:
Synthetic Polymer Systems. At the end, the reader will find an extensive and useful subject index. The objective of the editors was to emphasize a multidisciplinary approach, and also to encourage the reader to consider the use of new techniques. This book is an excellent overview of the field and is a recommended addition to the researcher’s library.
RGURNY IJniuersity
of Geneva