Books
Recapping gas chromatography
Analytical Gas Chromatography, 2nd ed. Walter Jennings, Eric Mittlefehldt, and Philip Stremple Academic Press 525 B St., Suite 1900 San Diego, CA 92101 1997, 389 pp., $59.95
This book is a revision of the original 1987 edition. In the preface, the authors stress that they intended to reformat this edition so it could serve as a college-level text, a "brush-up" manual for chromatographers, and a reference. In many ways, they meet or exceed these goals and provide the reader with a fair mix of theoretical and practical information. One preference of the authors is made quite clear in the introductory chapter— they view capillary columns as vastly superior to packed columns. Subsequent chapters are devoted almost exclusively to their use. Discussion of packed columns is limited to examples that show the benefits of capillary columns. The general theoretical treatment of the chromatographic process has been reduced to a simplistic approach, with experimental data being used for method optimization. However, the book provides a rigorous discussion of factors to consider when selecting a capillary column or optimizing its performance. One chapter is devoted to carrier gas flow, column dimensions, and temperature-programming effects. Another is devoted to stationary phases. 270 A
Significant coverage focuses on the practical considerations for column selection, installation, and use. To assist the reader, the authors provide a series of van Deemter plots for a representative set of solute retention factors. These calculated plots were prepared for a range of column lengths, and internal diameters, in which helium and hydrogen are used as carrier gases. Unfortunately, the 78 pages devoted to these plots serve more as a distraction. The authors note that the plots were prepared with previously defined equations and a spreadsheet program. It would have been much TYlflfP useful to outline how the reader could have prepared these plots The common methods for sample introduction are clearly and concisely covered. The relative advantages of each and their optimization and the differences one can expect between traditional versus largebore capillary columns are presented in a manner that imparts a great amount of practical information. In addition, a range of alternative methods is outlined in a chapter devoted to special analytical techniques. The latter portion of the text is devoted to a range of selected applications in the areas of food, flavor, fragrance, petroleum, and environmental and biological samples. The authors go beyond a simple review of the recent literature. In addition to chromatographic results, the reader is provided with the methods used for sample collection, the rationale for doing the analysis, and a comparison with other methods. This section would be quite useful for instructional purposes. Finally, the authors provide general information on troubleshooting; a discussion of test mixtures, column bleed and rejuvenation; and sources of peak distortion retention gaps and flameionization detector difficulties Although the text is well-written, it lacks coverage of qualitative and quantitative analysis of chromatographic data. Furthermore, no comprehensive discussion of
Analytical Chemistry News & Features, April 1, 1998
GC detectors is provided. Finally, with the importance of GC/MS and GC/FT-IR, it is surprising that these methods and the use of hyphenated methods are essentially ignored. Reviewed by James K. Hardy, University ofAkron
Inside LC Columns
HPLC Columns: Theory, Technology, and Practice Uwe D. Neue John Wiley & Sons 605 Third Ave. New York, NY 10158 1997, 393 pp., $89.95
Although the technique of high-performance liquid chromatography (HPLC) is nearly 25 years old, it is surprising that no book devoted to LC column technology has previously been written. HPLC Columns: Theory, Technology, and Practice satisfies this need. This text authoritatively describes the principles of column design and use and emphasizes subjects of interest to practicing chromatographers. This book is intended as a practical guide, but its background theory reinforces concepts. It should also prove useful as supplemental reading in a graduate-level course in separation science. No attempt is made to provide exhaustive literature reviews. Instead the citations illustrate
key points and provide starting points for additional reading. The initial chapters outline HPLC instrumentation milestones and provide a new perspective on how the physical parameters of various components influence modern column design. Virtually every recent innovation in column technology is described, including axial and radial compression, monolithic structures, membranes, and fibers. Considerable detail is provided on the physical and chemical aspects of silica substrates, stationary-phase synthesis, and column preparation. Of particular interest is a section devoted to column packing. General guidelines for slurry packing are presented, which facilitate rational decisions on choice of slurry and drive solvents reservoir configuration and packing conditions Much of the text is organized into chapters based on column separation modes (e.g., size exclusion, normal phase, reversedphase, ion-exchange, and hydrophobic interaction chromatography). Sufficient detail familiarizes the reader with theory of operation, types of columns, approaches to column selection and method development, and general operational matters. Of considerable practical interest are the final chapters, which are devoted to preparative separations, method development, column care, and troubleshooting. As with other portions of the book, sufficient background theory helps provide an understanding of basic principles. Guidelines are presented for method development for various separation problems. Topics include solvent selection, isocratic versus gradient separations, gradient optimization, temperature effects, and how to proceed with totally or partially unknown mixtures. The chapters on column care and troubleshooting provide ample information about potential problems that may result from column degradation instrumental malfunction and improper method development These sections are well illus-
trated with chromatograms that exemplify operating with it, then this handbook might the consequence of sample overload, colbe a starting point. If I wanted names, adumn bed collapse, excessive injector voldresses, and phone numbers of instrumenume, extra column effects, secondary tation suppliers, then this reference would chemical equilibria, and sample carryover. be appropriate. If I wanted to know the opCare is taken throughout to include discus- erating principles of the technique, howsion of measurement reproducibility. HPLC ever, I might be disappointed with some of Columnss Theory, Technology, and Practice the entries. provides a wealth of practical advice to As I read the handbook for the first serve experienced and inexperienced time, I felt let down. I expected more deanalysts. tail on each method, more detailed techReviewed by Lane Sander, National In- nical illustrations, and better example data. But then when I read it for the secstitute of Standards and Technology ond time, realized the scope it represented, and used it to search for material on techniques, I could see the value of the handbook. A question remains as to whether the handbook is a better source of starting information than, say, a Yahoo search on the Internet. It depends. If one knows enough about a technique to bound an Internet search and not be overwhelmed with hits, then it is not. But if one is starting cold, then it is. Each author has limited the scope of his or her section to central principles and applications. From there on out, the Internet can be used more efficiently. A CD is also included with the book to help Handbook of Instrumental look up topics. Techniques for Analytical Chemistry Were I in a position to evaluate potential purchases from recommendations submitFrank Settle, Ed. ted by others, I would prize this book. It Prentice Hall certainly lists who to call and how to inOne Lake St. quire about what one needs to know. It also Upper Saddle River, NJ 07458 would be a good deal cheaper than a trip to 1997, 994 pp.. $95 the Pittsburgh conference. The handbook is just that—a handbook. It A graduate student getting ready for a should not be confused with a textbook or research proposal oral exam could find this a review of the various fields and techbook an excellent way of quickly learning niques. Just as the Handbooo of Chemistry enough vocabulary about the various techand Physics is used to extract specific niques that could be thrown out by my pieces of information, so should this handquestioners. The handbook delivers what it book be used. promises and should be considered a success in that light. For example, if I wanted to learn some of the vocabulary about a technique or Reviewed by John P. Walters, St. Olaf what some of the complications were in College
Quick guide to instrumentation
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