Edited by Richard W. Horobin and John A. Kiernan
How to use this book vii Contributors list ix Preface x
1. Introduction to dyes and stains. F.H. Kasten 1
2. The history of staining. B. BracegirdZe 15
3. Nomenclature and classification of dyes and other coloring agents. Kiernan 23
4. Applications of dyes, fluorochromes and pigments. M. Wainwright 41
5. Mechanisms of biological staining. R. W Horobin 53
6. Dye purity and dye standardization for biological staining. H. Lyon 67
7. Reactive staining reagents and fluorescent labels. rC Stockert 77
8. The use of dyes and fluorochromes as indicators. M. Wainwright 89
9. Nitroso and nitro dyes. R. W Horobin 101
10. Monoazo dyes. R. W Horobin 107
11. Dis-, tris-and polyazo dyes. R. W Horobin 125
12. Diazonium salts and their reaction products with coupling agents. R.W Horobin 145
13. Tetrazolium salts and formazans. R. W Horobin 157
14. Amino di-and triarylmethane dyes. R. W Horobin 169
15. Hydroxy triarylmethanes. R. W Horobin 203
16. Xanthenes. R.W Horobin 219
17. Acridines and phenanthridines. R.W Horobin 253
18. Azines. R. W Horobin 267
19. Oxazines and related dyes. R. W Horobin 277
20. Thiazines. R. W Horobin 293
21. Romanowsky-Giemsa stains. D.H. Wittekind 303
22. Polyene dyes and fluorochromes. R.W Horobin
23. Polymethine dyes -1. Cyanines, oxonols, benzimidazoles, indolenines and azamethines. R. W Horobin 313
24. Polymethine dyes 2. Styryls, thiazoles, coumarins and flavonoids. R. W Horobin 349
25. Carbonyl dyes including indigoids, anthraquinones and naphthalimides. R. W Horobin
26. Phthalocyanines, porphyrins and related azaannulenes. R. W Horobin 367
27. Miscellaneous inorganic and organic substances used as biological stains. J.A. Kiernan and R. W Horobin
28. Methods for testing biological stains. D.P. Penney and J.M. Powers, with the assistance ofC Willis, M. Frank and C Churukian 389
There have been nine previous editions of Biological Stains, published from 1925 to 1977. In each of these books, chapters concerning general aspects of dyes and other stains were followed by a compendium of more detailed accounts of individual compounds, grouped in chapters on the basis of chemical structure. The tenth edition has a similar plan, although it is a multiauthor work, for which all the chapters have been newly written. The average reader is assumed to be a biologist or from a biomedical field; but not a specialist in analytical, organic, physical or dyestuff chemistry, and not an expert in animal or plant histology, pathology or toxicology. The book is a source of information about dyes, fluorochromes and other colorants; and an account of their uses. It does not contain technical instructions, for which the reader must consult the manuals and articles cited in the text.
Overview. The first two chapters provide respectively a sketch of staining in biological laboratories and the history of staining for microscopy. Chapter 3 explains the categorization of dyes and fluorochromes, which differs from that in previous editions, along with some principles that govern the spelling of informal names of dyes. Applications, including those outside the laboratory, are reviewed in Chapter 4; and this is followed by a chapter reviewing the mechanisms of attraction and attachment of dyes to biological substrates. Examples and mechanisms of staining and labeling by covalent attachment are discussed in Chapter 7, and dyes used as indicators are reviewed in Chapter 8.
Conn’s Biological Stains is published for the Biological Stain Commission, an independent non-profit organization in the USA that tests and certifies many stains, especially those used in histopathology. Standardization is also attempted elsewhere and by other organizations; this is described in Chapter 6, together with an account of the impurities that occur in dyes -the raison d’etre of the Biological Stain Commission. Most of the remaining 20 chapters contain accounts of particular dyes and fluorochromes, and the final chapter relates to the methods used by the assay laboratory of the Biological Stain Commission.
Included and excluded items. Dyes and fluorochromes have been chosen for inclusion on the basis of being mentioned in recent published literature, both staining manuals and research papers. Only substances of known chemical composition are discussed. Consequently some proprietary colored and fluorescent reagents used by research workers are not included. One of us discussed this issue with a major supplier, with his persuasive efforts proving inadequate when faced with commercial pressures. The ninth edition of Conn’s Biological Stains (Lillie, 1977) included several dyes, some of questionable identity, that had not been available for many years, and also some newer ones that never
came to be used as stains. Most of these items have been omitted from the tenth edition to make room for newer compounds, especially fluorescent labels and probes, currently widely used in laboratories.
The electronic version. To keep this book a reasonable size, about half the recent material that was unearthed from the literature has been omitted. We have also omitted entries for compounds that have been little used in recent years, and we do not include many older but nevertheless useful references to traditional uses of dyes. A complete and fully searchable version of Conn’s Biological Stains will be available on a web site to purchasers of the printed book. This electronic version will cover more compounds, give more examples of older and current uses and will be updated at regular intervals. Purchasers of the printed version will be entitled to free online access for a trial period, after which access will be limited to subscribers. The online version will have regular updates. Purchasers of the print version should register by sending an email to Conns@bios.co.uk. Notification will be sent out when the online version is released.
Disclaimers. The inclusion of a substance in this book does not constitute a commendation of its efficacy for any purpose. Note that dyes and fluorochromes often vary in composition (see Chapter 6), and consequently there are inconsistencies in phYSicochemical data such as solubility and absorption maxima reported in the literature. The values given here should be taken as indicative, not authoritative.
For the case of solubility an additional, and specific, caveat should be given. Dye molecules stick to themselves, as well as to cells and tissues; resulting in ready formation of colloidal suspensions and related forms. This makes measurement of solubilities a technically difficult, indeed a conceptually ambiguous, task. Solubility data deserve especial skepticism even in the, unusual, circumstance of their relating to pure dye samples.
Toxic, allergic and other hazards are mentioned for some, but not all items. Although the great majority of dyes do not pose serious hazards, laboratory workers must always follow good laboratory practices and obey the rules set out by local safety officers and committees.
Most of the dyes discussed in this book are or formerly were items of commerce, and many of their names are or were legally protected terms. Biological and biomedical end-users and writers routinely ignore this. They will refer, for instance, to Texas red without noting that this is a legally protected term owned by Molecular Probes Inc., or to dye names containing the words coomassie or sirius without regard to the Ciba-Geigy or Bayer corporations respectively. Failure to mention the owner of a trademark does not imply any disrespect for the originators of such names, without whom there would be no biological stains.