XXII trends in analytical chemistry, vol. 4, no. 8,1985

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books Strongly recommended to all GC-MS users

Practical Aspects of Gas Chromato- graphy-Mass Spectrometry, by G.

Message, Wiley-Interscience, E84. US$59.95 (376 pages) ISBN O-471 -06277-4

This well conceived book contains a wealth of information of value to both the novice in gas chromatogra- phy-mass spectrometry (GC-MS) and to the experienced practitioner. It is divided into four parts, covering ‘GC-MS systems and components’, ‘Routine GC-MS operation, tech- niques and procedures’, ‘Trouble- shooting faults on GC-MS systems’ and ‘Choosing a GC-MS system’. I found the first section the most suc- cessful because its objective was most clearly defined - the descrip- tion of GC-MS instrumentation in sufficient detail for the user but not the expert. I am not aware of any other volume which brings together so much useful information in one place. Thus, for example, Message describes the designs and principles of operation of vacuum pumps and gauges - essential background knowledge to permit adequate rou- tine maintenance. The explanations of the principles behind the types of

mass analysers used in GC-MS in- struments are thorough. With the au- thor’s background one might have expected a bias towards quadrupole instruments but this is only infre- quently evident. Indeed, Message’s knowledge of quadrupoles has en- abled him to prepare a section on the quadrupole mass filter which in- cludes details rarely found in an in- troductory text but which avoids be- coming submerged in too much of the physics involved.

I particularly liked the inclusion in Part 1 of four glossaries, covering terms relating to vacuum systems, mass spectrometry, gas chromato- graphy and data systems. The exper- imental& new to GC-MS will find these invaluable.

Part 2 of the book, describing the use of GC-MS, is concerned princi- pally with procedures for obtaining optimal instrument performance. The implicit assumption is that ex- perimental design is not a major con- cern to the reader. Derivatisation techniques, for example, which are so frequently crucial to the success of GC-MS analyses, are not discussed and there is little guidance on the choice of ionisation technique. One might quibble with some of the opin-

ions expressed in this section of the book (such as the author’s dislike of silylation as a deactivation tech- nique) but Message succeeds in his principal objective - that of pro- moting a thoughtful approach.

Parts 3 and 4, covering trouble- shooting and choosing an instru- ment, respectively, again contain useful advice. The author’s experi- ence enables him to suggest a num- ber of ways of improving interaction with the instrument manufacturers - including the suggestion that an arriving service engineer should al- ways be greeted with a cup of coffee! It would be difficult to make these sections of the book comprehensive and Message himself admits to a high proportion of opinion. Once again, however, the comments are helpful in stimulating a thorough approach to the problems.

I liked this book and found it help- ful. It was returned only reluctantly when lent to colleagues in the labora- tory. I recommend it strongly to all GC-MS users.

SIMON J. GASKELL

Simon J. Gaskell is at the Laboratory of Molecular Biophysics, National Institute of Environmental Health Sciences, Re- search Triangle Park, NC 27709, U. S. A.

Computers in chemistry, useful for everyone

Computer in der chemie, Praxis- orientierte Einfiihrung, edited by E. Ziegler, Springer- Verlag, 1984. DM 128.OOlapprox. US$49.70 (X + 280pages) ISBN3-540-12974-X

The aim of this book is to override the fear which computers still pro- duce in many chemists. It tries to bring the computer nearer to the practising chemist and to explain what it can do for him. The book dis- cusses eight topics in which comput-

ers are not only important but nec- essary. The short introductory chap- ter is written by the editor, Professor Ziegler. It concentrates on explain- ing what kinds of hardware and soft- ware are available and in doing so in- troduces the terminology of the field to the newcomer. This chapter is nec- essarily somewhat superficial but it is up to date. A single remark: Profes- sor Ziegler is director of the magnifi- cent centralized computer network of Mulheim and this clearly leads him to dislike personal computers. His

arguments against are correct. How- ever, he might have noted that the personals are rapidly becoming as performant as the minis of two years ago, that software for personals is rapidly becoming of professional quality and that, most importantly in this context, it is much easier for a newcomer to learn informatics on a micro than on a large system, where he must first learn how to communi- cate with the central computer, be- fore he can begin to learn the lan- guage!

trends in analytical chemistry, vol. 4, no. 8, I985

Chapter 2 (author: E. Zass) gives a very complete account of chemical databases concerned with structural information and in Chapter 3 Profes- sor Ziegler explains in a didactical way some of the basic notions about data acquisition.

R. W. Arndt’s chapter on automa- tion with microprocessors has left the reviewer on his hunger. Everyone who has worked with computers knows that the first barrier which must be taken is the fear of comput- ers in general and programming in particular. Learning the rudiments of a simple language such as BASIC overcomes this problem: it shows that there is nothing mysterious about software and that with suffi- cient application any scientist is able to write or understand software. The next barrier one meets is the inter- facing of instrument and computer and one would have expected a more detailed description of how inter- faces work in this chapter. However, this is probably a matter of personal appreciation and the material pre- sented in this chapter is relevant and well organized.

G. Szekely and J. T. Clerc’s chap- ter on databanks is short but to the point. It does not go into technical details, which is not necessary in a book such as this one, but explains

the philosophy behind the different approaches. As such, it is not only of interest to beginners but also to com- puter specialists who like to know more about applications.

The chapter on chemometrics was written by K. Varmuza, who is also the author of a very fine book on pat- tern recognition published in 1980 by the same publisher. This chapter, as the preceding one, is very well writ- ten: it finds a good balance between technique, philosophy and applica- tion, so that it is a pity that, since each author had only 20-30 pages available, Varmuza was forced to re- strict the discussion to only two themes, namely pattern recognition and experimental optimization. And chemometrics is much more than this!

Chapter 7, written by P. Bishof, concerns the computation of quan- tum-chemical molecular parameters. Analytical chemists today try more and more to apply these computatio- nal methods to predict or understand quantities of analytical chemical in- terest, not only in spectroscopy but also in chromatography. This chap- ter explains in a simple and clear way the main methods such as NDDO, CNDO, etc. and also, very impor- tantly, how to get started (for in- stance, where to obtain programs).

XXIII

The reviewer is unqualified to judge the fundamental qualities of Chapter 8 (author: C. Kruger) on X- ray structural analysis. It is, howev- er, clearly well documented and shows very convincingly that some methods are completely dependent on computers. .

J. Casteiger’s chapter on synthesis planning is the only one to mention artificial intelligence. This is in the reviewer’s opinion the only real drawback of this book. At the mo- ment that interest in artificial intelli- gence is soaring, a brief mention in one chapter is not enough.

Although the book is written for non-computer specialists, it is also worthwhile for the specialist. The material is explained in a straightfor- ward way, which is useful for teach- ing at the graduate level. Moreover the solutions found in other fields may help the specialist to solve his own problem or to find new orienta- tions. For instance, synthesis plan- ning may show the way to analysis planning.

D. L. MASSART

D. L. Massart is at the Fakulteit der Ge- neeskunde en Farmacie, Dienst Farma- ceutische en Biomedische Analyse, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.

Comprehensive and well written

Developments in Food Analysis Techniques, Vol. 3, edited by R. D. King, Elsevier Applied Science, 1984. f 26.00 (X + 217 pages) ISBN 0 853 34242 8

The aim of this series is to allow the scientist faced with a particular ana- lytical problem to make an assess- ment on the available methodolo- gies, choosing the best method for his task, correctly interpreting his ana- lytical finding and, finally, looking at these findings into a correct perspec- tive with regard to food analysis.

The third volume of this series is a coherent, well balanced book, un- doubtedly a valuable source of refer-

ences for the reader who wants to deeply pursue a topic. The book is well illustrated, there are few typo- graphical errors and only occasional- ly the wording is cumbersome.

In chapter 1 Selvendran and Du- Pont consider the problems involved with the analysis of dietary fibre (DF) and they review some recent developments in that area, including improved methods for preparing and analysing gram quantities of DF from fresh and processed foods. The prob- lems in DF analysis are discussed un- der three headings: (i) problems aris- ing from the DF preparation; (ii) those associated with the determin- ation of the constituent carbohy- drates; and (iii) those involved in lig-

nin determination. A review of trace element analysis

is given in chapter 2 by Wolf and Harnly. The authors describe some of the most recent advances in quan- titative trace analysis in food and in biological materials. Atomic absorp- tion spectrometry (AAS), atomic emission spectrometry (AES), in- ductively coupled plasma (ICP), neutron activation analysis (NAA) and mass spectroscopy (SSMS and IDMS) are very sensitive techniques for the determination of a wide num- ber of elements at nanogram or pico- gram level. The techniques have the advantage of multi-element analysis.

Chapter 3. deals with the current state of methodologies for the deter-