Millennium Microscopy?

In the past two years, three books have appeared on biological electron microscopy. The 2nd edition of the text by Glauert and Lewis appeared in 1998, the 2nd edition of the book by Bozzola and Russell appeared a year later and now, in the new millennium, we have the 4th edition of the book by Hayat. How well does this latest text measure up to the recently published texts and, indeed, to the many texts written and edited by Hayat over the past 25 years? The simple answer is that this latest book is an improvement over earlier editions.

Hayat’s book provides an immense amount of information about how to prepare, primarily mammalian biological materials and viruses, for examination by transmission electron microscopy. Only lip service is given to preparative techniques for examining specimens in other forms of electron beam instrumentation. This is not an all embracing text. With the notable exception of plant material, there appears to be no specific references to other vertebrates, the invertebrates and microorganisms. The first seven chapters are, in essence, a re-working and updating of the earlier editions of this book. Details are given about specimen fixation, dehydration, embedding and sectioning. The chapter on support films is most useful and contains a lot of easy to follow recipes. The two chapters on positive and negative staining complete the library of methods needed for wet-chemistry thin-sample preparation for conventional transmission electron microscopy. The section on immuno-cytochemistry, while replete with recipes and procedures, reveals a lack of first-hand experience with this, the most important aspect of modern microscopical techniques. Hayat generally provides in these first seven chapters numerous recipes for all sorts of specimens, together with the biochemical background to provide the provenance of a particular protocol. There is a lot of very useful information and the procedures he describes appear easy to follow. Much of this information has, however, to be taken on trust, as the author often fails to provide key references to given procedures. Indeed, it is rather worrying, that many of the references in this book are pre mid-1990s, which suggests that the author is either unaware or chooses to ignore a lot of recent work on sample preparation.

Nowhere is this more true than in Chapter 8, which deals with low temperature methods, a subject close to this reviewers heart. An immense amount of new material has been published in the past 10 years and for reasons best known to the author, much of this exciting new information is ignored. In reading this chapter it is difficult to believe that Hayat has ever had any first-hand experience with low temperature microscopy. The chapter he has written is, as Montaigne wrote in the 16th century ‘a posie of other men’s flowers’, and although it provides a very broad overview of cryo-microscopy, it is not something one would recommend to a person embarking on this critically important sample preparation technique.

The final two chapters on the preparation of plant tissues and the application of microwave heating to microscopy are a useful addition to this edition of the book. It is particularly beneficial that Hayat had given details of the immunocytochemical procedures that can be used to localise molecules and macromolecules in plant tissues. The chapter on microwave fixation gives a good overview of the procedures, and advantages and disadvantages of this approach to sample preparation.

The book is set out in a reader friendly form and it is useful to have all the references in one place at the end of the book. The illustrations and diagrams are generally useful and complement the text, although some of the micrographs are rather dark. Principles and Techniques of Electron Microscopy lacks the authority and accuracy found in the Glauert and Lewis book and is different from the broad canvas painted by Bozzola and Russell. It would, for example, have been helpful if Hayat had included information about what happens when the carefully prepared specimen is put into the transmission electron microscope and an image is obtained. Thus, Hayat, in this robustly named text makes virtually no mention of image processing, image analysis, quantitative microscopy, the production of micrographs and, probably most important of all, interpretation and quality assessment procedures of the final images. Maybe this is asking too much.