Book Review of Principles of Molecular Photochemistry—An Introduction

Oct 6, 2010 - The primary competitor to this text would be Turro, Ramamurthy, and Scaiano's own Modern Molecular Photochemistry of Organic Molecules ...
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Cheryl Baldwin Frech University of Central Oklahoma Edmond, OK 73034-5209

Principles of Molecular Photochemistry—An Introduction by Nicholas J. Turro, V. Ramamurthy, and J. C. Scaiano University Science Books: Sausalito, CA, 2009. 495 pp. ISBN 978-1891389573 (paper). $82.50. reviewed by Jack K. Steehler

Do you want to really learn modern spectroscopy? Do you want to focus on organic photochemistry? Do you need to understand concepts and principles more than quantum mechanical theory? If you answered each of these questions in the affirmative, then Principles of Modern Photochemistry—An Introduction by Turro, Ramamurthy, and Scaiano is a wonderful resource and primer for you. Nicholas Turro (Columbia University) has been the primary author of multiple versions of organic photochemistry texts over the last 30þ years. These texts collectively are well known as the best learning aids for new practitioners in this field. This 2009 version clearly presents all of the conceptual background needed to really understand organic photochemical processes. Seven different chapters cover basics such as energy level structures in molecules, the wide variety of radiative and nonradiative transitions between energy levels, energy and electron transfer, and the theory of organic photochemistry. The presentation style is deeply conceptual. Basic concepts are presented then combined in increasingly complex ways, always focusing on understanding processes and molecules. Anyone who has looked at Jablonski energy level diagrams in detail knows the blizzard of confusing processes that can occur. Turro et al. present basics like spin-orbit coupling and the Franck-Condon principle at length, with full and exceptionally clear explanations of the many contributing factors. More complex situations such as twisted intramolecular charge-transfer (TICT) states or triplet-triplet annihilation are also clearly presented, with solid detail, yet with complete focus on conceptual understanding. The amazing thing about this book is its ability to present complex spectroscopy in detail but with truly minimal mathematics. The 64-page “theory of photochemistry” chapter has only three numerical equations! Those seeking detailed quantum mechanical derivations of spectroscopy should look elsewhere... the focus here is on understanding concepts. While conceptual, this text is not low level. Its stated audience is those students who have completed organic chemistry and a year of physics. That seems slightly optimistic, yet the book is clearly accessible to upper-level chemistry majors in an advanced organic chemistry or spectroscopy course, or to graduate students. Practicing spectroscopists will also find it a continually useful resource. Inorganic spectroscopists may be disappointed to note the absence of inorganic spectroscopy examples, but the primer on photochemical processes remains highly relevant. 1298

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The primary competitor to this text would be Turro, Ramamurthy, and Scaiano's own Modern Molecular Photochemistry of Organic Molecules (ISBN 978-1891389252), long the bible of organic photochemistry and available in a new 2010 edition. That longer work (14 chapters versus 7 chapters in the book reviewed here) begins with the same content, but adds a chapter on mechanisms and five chapters on specific classes of organic photoreactions. In comparison, Principles of Modern Photochemistry—An Introduction reviewed here is advertised as the conceptual primer (almost 500 pages makes it a rather detailed primer), while the longer work adds specific reaction examples and details. Choose either one...their clarity will serve you well. Jack K. Steehler teaches in the Department of Chemistry, Roanoke College, Salem, VA 24153; [email protected]. DOI: 10.1021/ed100868v Published on Web 10/06/2010

Bioinorganic Chemistry: A Practical Course by Nils Metzler-Nolte and Ulrich Schatzschneider Walter de Gruyter: New York, NY, 2009. 138 pp. ISBN 978-3110209549 (paperback). $63. reviewed by Richard S. Herrick

This delightful book breaks new ground as it is the first lab manual devoted entirely to experiments in bioinorganic chemistry. Bioinorganic chemistry is an interdisciplinary subject and has been well covered by many excellent textbooks used in courses at the undergraduate or graduate level. However, there is a need for experimental training for students wishing to enter this discipline. This slim volume, based on experiments designed for a lab-based course the authors have taught over a period of 10 years, meets this need and should be welcomed by faculty hoping to teach their students the practical skills of bioinorganic chemistry. In this book you won't find the traditional experiments, such as preparations of tetraphenylporphyrin, cisplatin, or copper(II) glycinate. Instead, the authors have created a project-based book with a series of completely new experiments that encompass a diverse range of topics relevant to modern bioinorganic chemistry. Syntheses include the preparations of ligands, coordination compounds, organometallic compounds, peptides, and peptide conjugates. Students also have the opportunity to learn how to covalently modify proteins. A wide variety of qualitative and analytical measurements are introduced, including assays using proteins or cleavage of DNA, physical and spectroscopic methods including UV-vis spectroscopy, and cyclic voltammetry. Each of the eight chapters is organized around a particular theme and begins with a one-paragraph summary followed by

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learning targets in bulleted lists shaded in gray. A background section, typically 5-9 pages, gives a simple introduction to the topic aimed at nonexperts performing the experiments. Current research literature references are included so that more indepth information on a topic can be obtained. While the authors make it clear that this is not a textbook, these summaries ensure that students will have a solid understanding of a topic when performing the experiments. The experimental section begins with bulleted objectives, again shaded in gray. A list of required materials, including information such as molecular weights and CAS numbers, are provided, and clear instructions are given for preparations of biochemical solutions or syntheses required during each step of the experiment. It is especially helpful that detailed spectroscopic information is given for precursors that must be prepared as part of an experiment. Each experiment ends with a section that provides variations of the experiment and with a bulleted section titled Additional Questions that encourages students to think more deeply about the subject of the experiment. The experiments lack a safety section, although the authors emphasize the need for safe experimentation. The first theme is the activation, deactivation, and signaling of small molecules (O2, H2O2, O2-, CO, NO) by proteins. In Chapter 2, Mn(salen)Cl is prepared as a model of superoxide dismutase enzymes; xanthine oxidase is employed to generate superoxide. A myoglobin-based assay system is employed as an NO sensor in Chapter 3 and therapeutically prescribed sodium nitroprusside is the source of NO. UV-vis analysis in each experiment is used to monitor interactions of the complex with the small molecule. A second theme is metal complexes as intercalators and manipulators of DNA. In Chapter 4, metallointercalation into calf thymus DNA is investigated using a polypyridyl ruthenium(II) complex and UV-vis or fluorescence analysis. In Chapter 5, the theme switches to designed DNA cleavage driven by metal complexes. Mn(salen)Cl and a Cu(II) phenanthroline complex drive the oxidative cleavage of a standard DNA plasmid. Agarose gel electrophoresis is used to analyze the DNA cleavage products. The focus shifts to preparing metal-peptide and metalprotein bioconjugates. In Chapter 6, a modified version of a neurologically active pentapeptide, [Leu]5-enkephalin with ferrocene carboxylic acid grafted onto the amine end is created by solid-phase peptide synthesis. The redox-active ferrocene group acts as a sensitive marker for biological studies. In Chapter 7, ferrocene carboxylic acid is converted to an activated ester and covalently attached to hen egg white lysozyme via pendant lysine. Identification of which lysine residue forms the point of attachment is determined by trypsin digestion and mass spectroscopic analysis. The penultimate chapter turns to the cyclic voltammetric investigation of metal bioconjugates. The classic redox-active compound, ferrocene, is tested first. Then, for comparison, students investigate the redox behavior of the metal-protein bioconjugate prepared in Chapter 6. The focus of Chapter 9 is metal complexes used in the treatment of diseases, demonstrated by screening to test the antiproliferative activity of cisplatin or derivatives on the immortal HeLa cell line. Crystal violet is used to interrogate the cytotoxicity of the platinum complex, and the outcome is determined by UV-vis analysis. r 2010 American Chemical Society and Division of Chemical Education, Inc.

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These modern experiments and the range of techniques and types of compounds that they cover ensure that this will be a book coveted by bioinorganic chemists or chemists with an interest in bioinorganic chemistry. Richard Herrick is a professor of chemistry in the Department of Chemistry at the College of the Holy Cross, Worcester, MA 01610; [email protected]. DOI: 10.1021/ed1009317 Published on Web 10/06/2010 Introduction to Modern Liquid Chromatography, 3rd edition by Lloyd R. Snyder, Joseph J. Kirkland, and John W. Dolan Wiley-Blackwell: Hoboken, NJ, 2010. 912 pp. (Includes extensive diagrams, charts, tables, and photographs throughout the book all in black and white; two appendices, reference section, and index.) ISBN: 978-0470167540 (hardback). $125. reviewed by Robert G. Weston

Snyder, Kirkland, and Dolan's third edition of Introduction to Modern Liquid Chromatography is an impressive volume for an “introductory” text, totaling over 900 pages. The opening chapter presents an extremely brief history of HPLC, alternative techniques to HPLC, and additional sources for HPLC information. The pith of the material starts with the second chapter in which many of the chromatographic figures of merit such as retention, selectivity, and resolution are both qualitatively described and quantitatively defined using several mathematical equations. Also introduced in this chapter are method development and gradient elution, both of which are further developed later in the book. Chapters 3 and 4 address the hardware of the HPLC system, including components such as mobile phase degassers, pumps, autosamplers, thermostated column compartments, and detectors. Approximately 15 different types of detectors are described briefly, with a slight emphasis on UV and mass spectroscopic detection. The fifth chapter is solely dedicated to the column with descriptions of stationary phases and the particles to which they are bonded, how different stationary phases affect various separations, and proper plumbing of the column into the HPLC system. The next four chapters are, in my opinion, the heart of the book. In these chapters, the various mobile phase approaches (reversed phase, normal phase, and gradient elution) are discussed in a great degree of detail. The strength of each technique as well as its limitations and potential shortcomings are brought to light, allowing readers to grasp which technique may be most applicable to the separation goal at hand. Also within these chapters are method development insights applicable to each of the mobile phase systems. Chapter 10 is dedicated to method development incorporating computer models of HPLC systems. The next chapter discusses qualitative and quantitative aspects of HPLC analysis. Among the quantitative aspects discussed are different types of calibration curves, including external standard, internal standard

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and standard addition. Limits of detection and quantification are also addressed, as is the topic of sources of error in chromatographic quantitation. Method validation, biomolecular separations, stereoisomer separation, preparative scale separations, sample preparation, and system troubleshooting comprise the final six chapters of the book. These topics would not likely be considered to any large extent in an introductory chromatography course, but may be of special interest to practitioners in the field or to graduate students beginning their work in liquid chromatography. The authors use numerous figures, tables, and example chromatograms to highlight and clarify the discussions in the text. I find the chromatograms particularly useful and demonstrative of the changes that can be affected by adjustments in the physical conditions of the chromatographic system. The authors have set aside some sections throughout the book as being more in-depth than the regular practitioner may need to know or which may have limited practical application; these sections (indicated by italic type at the beginning) may be skipped if a reader wishes to forego the additional information. These more detailed sections often deal with mathematical derivations or with physical descriptions and interpretations of what is happening at a molecular level in the chromatographic column. New students of HPLC may likely find these sections of material quite weighty. This book is too comprehensive for an introductory instrumental analysis course, not because of the inaccessibility of the material to the new HPLC user, but simply owing to the volume of material offered. The instructor of a semester-long upper-division or graduate-level liquid chromatography course, however, would likely find specific portions of the book quite useful for their students, especially Chapters 2, 6, 7, and 9, and portions of Chapters 3, 4, and 5. The extensive references throughout all of the chapters give readers the opportunity to further their understanding of the concepts introduced in the text by reading primary source literature. This work could also be extremely useful to a new user of HPLC, whether in an academic or corporate laboratory setting, who needs to develop proficiency in a short period of time. The specific chapters covering qualitative and quantitative analysis, method validation, sample preparation, and troubleshooting would likely be applicable to all regular users of HPLC, while the chapters on enantiomeric, preparative, and biomolecular separations may be left to readers wanting knowledge specific to those areas. While I would not suggest this as a student textbook for an instrumental analysis or introductory chromatography course, I do recommend that chemistry departments have this book available as a reference for students in an instrumental analysis courses using HPLC and for any students using HPLC as a part of their research. Robert G. Weston is a criminalist at the Oklahoma State Bureau of Investigation and an adjunct instructor of chemistry and forensic science at the University of Central Oklahoma, both in Edmond, Oklahoma; [email protected]. DOI: 10.1021/ed100940k Published on Web 10/21/2010 1300

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Innovative Methods of Teaching and Learning Chemistry in Higher Education edited by Ingo Eilks and Bill Byers Royal Society of Chemistry Publishing: Cambridge, U.K., 2009. 266 pp. ISBN 978-1847559586 (paperback).$ 99.00. reviewed by Wheeler Conover

Obviously, the United States is not the only country where discussions concerning postsecondary education have been ongoing. Between the Bologna Process (1) and the Lisbon Agenda (2), countries in the European Union are also discussing how tertiary education should be revamped in a world where students are tuning out lectures written, and probably delivered, 40 years ago. The European Chemistry and Chemical Engineering Education (EC2E2N) project was formerly the European Chemistry Thematic Network. EC2E2N is an organization of some 160 EU university chemistry departments as well many national chemical societies that provides a portal for common curriculum development, assessment, and increased interaction between academia and industry (3). This book represents one workgroup's attempts to identify innovations in EU postsecondary chemistry education. The chapters represent topics that are prevalent in today's higher education discussions. Some topics are related to contextualized learning or problem-based education. Other topics relate to assessment and the development of alternative methods of assessment to properly measure student learning. A more useful online experience that allows for more self-direction by students was discussed through efforts of institutions such as Scotland's Robert Gordon University and the Finnish Virtual University. The chapter discussing off-campus industrial placements and integration of industrial problems into the academic curriculum places great emphasis on the idea that chemistry education cannot be an island unto itself. A preparatory “industrial communication” course, similar to one in the University of Cincinnati's chemistry department, integrated with an internship similar to the one at The University of Texas at Dallas, provides a greater degree of success for both undergraduate and graduate students. This lends credence to a statement in the Bologna declaration that the first degree (i.e., the bachelor's degree) be relevant in the EU labor market. In an age when employers continue to complain that students are not prepared for industry, American chemistry departments would be wise to integrate this strategy into their own curricula. Finally, the book concludes with a discussion of training programs for new chemistry faculty. When there are senior faculty members who cannot even prepare a proper syllabus that can survive a student appeal, several training programs not only cover these issues plus integrate newer methods of studentcentered learning in depth. Some faculty members are even required to complete a certificate of teaching and learning before they are allowed to enter the classroom. The collection of papers does suffer from being a “dry read” even though it contains a good amount of knowledge for any

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chemical educator. It is evident, however, that the European Union is getting serious about postsecondary education reform. This tome represents only a small fraction of the work that will honor the intent of the Bologna Declaration. Educators in the United States will recognize the efforts being made and will encourage others to do the same.

2. Lisbon Strategy (Lisbon European Council 23 And 24 March 2000 Presidency Conclusions). http://www.europarl.europa.eu/summits/ lis1_en.htm (accessed Sep 2010). 3. European Chemistry and Chemical Engineering Education Network. http://ectn-assoc.cpe.fr/network/ectn5_EC2E2N.htm (accessed Sep 2010).

Literature Cited

Wheeler Conover is the Chief Academic Officer at Southeast Kentucky Community and Technical College, Cumberland, KY 40823; [email protected].

1. The Bologna Declaration of 1999: Joint declaration of the European Ministers of Education. http://www.ond.vlaanderen.be/hogeronderwijs/ bologna/documents/MDC/BOLOGNA_DECLARATION1.pdf (accessed Sep 2010).

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DOI: 10.1021/ed100964w Published on Web 10/15/2010

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