Haematoxylin

Haematoxylin
Identifiers
CAS number 517-28-2 YesY
PubChem 10603
ChemSpider 21106443 YesY
UNII YKM8PY2Z55 YesY
MeSH Hematoxylin
Jmol-3D images Image 1
Properties
Molecular formula C16H14O6
Molar mass 302.28 g mol−1
 YesY (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references
Haematein

Haematoxylin, hematoxylin, Natural Black 1, or C.I. 75290 is extracted from the heartwood of the logwood tree.[1] When oxidized it forms haematein, a compound that forms strongly coloured complexes with certain metal ions, the most notable ones being Fe(III) and Al(III) salts. Metal-haematein complexes are used to stain cell nuclei prior to examination under a microscope. Structures that stain with iron- or aluminium-haematein are often called basophilic, even though the mechanism of the staining is different from that of staining with basic dyes.

Haematoxylin and eosin stain is one of the most commonly used stains in histology. It is a permanent stain as opposed to temporary stains (e.g. iodine solution in KI).

Other common stain is phosphotungstic acid haematoxylin, a mix of haematoxylin with phosphotungstic acid.

In 1970s, due to clear felling of forests in Brazil and Central America, there was a shortage of logwood and therefore of haematoxylin. Its price went to record heights, which affected the cost of diagnostic histopathology, and prompted a search for alternative nuclear stains. Before the use of any alternatives became firmly established, haematoxylin returned to the market, though at a higher price, and resumed its place in histopathology. There were several dyes recommended as replacements: Celestine blue B (CI 51050), Gallocyanin (CI 51030), Gallein (CI 45445) and Solochrome cyanin (CI 43820). All four used Fe(III) as the mordant. Another alternative is the red dye brazilin, which differs from haematoxylin by only one hydroxyl group.

Contents

Haematoxylin staining solutions

These stains are commonly employed for histological studies. The mordants used to demonstrate nuclear and cytoplasmic structures are alum and iron, forming lakes or coloured complexes (dye-mordant-tissue complexes), the colour of which will depend on the salt used. Aluminium salt lakes are usually coloured blue-white, whereas ferric salt lakes are coloured blue-black.

Aluminium haematoxylin solutions

The three main alum haematoxylin solutions employed are Ehrlich's haematoxylin, Harris's haematoxylin, and Mayer's haematoxylin. The name haemalum is preferable to "haematoxylin" for these solutions because haematein, a product of oxidation of haematoxylin, is the compound that combines with aluminium ions to form the active dye-metal complex. Alum haematoxylin solutions impart to the nuclei of cells a light transparent red stain that rapidly turns blue on exposure to any neutral or alkaline liquid.

Alum or potassium aluminium sulfate used as the mordant usually dissociates in an alkaline solution, combining with OH of water to form insoluble aluminium hydroxide. In the presence of excess acid, aluminium hydroxide cannot be formed, thus causing failure of aluminium haematoxylin dye-lake to form, due to lack of OH ions. Hence, acid solutions of alum haematoxylin become red. During staining, alum haematoxylin-stained sections are usually passed on to a neutral or alkaline solution (e.g., hard tap water or 1% ammonium hydroxide) in order to neutralize the acid and form an insoluble blue aluminium haematin complex. This procedure is known as blueing.

When tap water is not sufficiently alkaline, or is even acid and is unsatisfactory for blueing haematoxylin, a tap water substitute consisting of 3.5 g NaHCO3 and 20 g MgSO4.7H2O in one litre of water with thymol (to inhibit formation of moulds), is used to accelerate blueing of thin paraffin sections. Addition of a trace of any alkali to tap or distilled water also provides an effective blueing solution; a few drops of strong ammonium hydroxide or of saturated aqueous lithium carbonate, added immediately before use, are sufficient for a 400 ml staining dish full of water. Use of very cold water slows down the blueing process, whereas warming accelerates it. In fact, the use of water below 10°C for blueing sections may even produce pink artifact discolourations in the tissue.

See also

External links

References

  1. ^ Cooksey 2010

Brown, G. G. 1978. An Introduction to Histotechnology. Appleton-Century-Crofts, New York.

Cooksey C (2010) Hematoxylin and related compounds - an annotated bibliography concerning their origin, properties, chemistry and certain applications. Biotechnic & Histochemistry 85(1): 65-82. http://informahealthcare.com/doi/full/10.3109/10520290903048418

Jocelyn H. Bruce-Gregorios, M.D.: Histopathologic Techniques, JMC Press Inc., Quezon City, Philippines, 1974.

Meloan, S. M. & Puchtler, H. 1987. "Harris hematoxylin," what Harris really wrote and the mechanism of hemalum stains. Journal of Histotechnology 10: 257-261.

Puchtler, H., Meloan, S.N. & Waldrop, F.S. 1986. Application of current chemical concepts to metal-haematein and -brazilein stains. Histochemistry 85: 353-364.


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Look at other dictionaries:

  • Haematoxylin — H[ae]m a*tox y*lin ( t[o^]ks [i^]*l[i^]n), n. [See {H[ae]matoxylon}.] (Chem.) The coloring principle of logwood. It is obtained as a yellow crystalline substance, {C16H14O6}, with a sweetish taste. Formerly called also {hematin}. [1913 Webster] …   The Collaborative International Dictionary of English

  • haematoxylin — haematoxylin. См. гематоксилин. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • haematoxylin — Basophilic stain that gives a blue colour (to the nucleus of a cell for example), commonly used in conjunction with eosin that stains the cytoplasm pink/red. Various modifications of haematoxylin have been developed. The histopathologist s H & E… …   Dictionary of molecular biology

  • haematoxylin — n. a colourless crystalline compound extracted from logwood (Haematoxylon campechianum) and used in various histological stains. When oxidized haematoxylin is converted to haematein, which imparts a blue colour to certain parts of cells,… …   Medical dictionary

  • haematoxylin — n. a colourless crystalline compound extracted from logwood (Haematoxylon campechianum) and used in various histological stains. When oxidized haematoxylin is converted to haematein, which imparts a blue colour to certain parts of cells,… …   The new mediacal dictionary

  • haematoxylin — n. crystalline substance obtained from logwood and used in the production of various dyes and stains (Chemistry) …   English contemporary dictionary

  • haematoxylin — [ˌhi:mə tɒksɪlɪn] (US hematoxylin) noun Chemistry a colourless compound present in logwood, which is easily converted into dyes and is used as a biological stain. Origin C19: from mod. L. Haematoxylum (genus name), from haemato + Gk xulon wood …   English new terms dictionary

  • haematoxylin — /himəˈtɒksələn/ (say heemuh toksuhluhn) noun 1. a leguminous plant of a genus Haematoxylon, of which only one species, H. campechianum, the logwood tree, is known. 2. the wood of the logwood. 3. Chemistry a colourless or pale yellow crystalline… …   Australian English dictionary

  • haematoxylin — haematoxˈylin noun A dye obtained from logwood • • • Main Entry: ↑haem …   Useful english dictionary

  • Phosphotungstic acid haematoxylin — (PTAH) is a mix of haematoxylin with phosphotungstic acid, used in histology for staining. It stains some tissue in contrasting colors in a way similar to haematoxylin and eosin stain, as phosphotungstic acid binds to tissue proteins. It is used… …   Wikipedia


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