Summary
The structure of Alcian blue 8GX has been investigated using chemical and physical methods. Elemental analyses of the boric acid-free dye and electrophoresis suggest a phthalocyanin with an average of slightly less than four S-methylene tetramethylisothiouronium side chains per molecule. Oxidative break-down in two stages to benzene carboxylic acids, leading to the identification of benzene 1, 2, 4 tricarboxylic acid (trimellitic acid) as the main product, prove the presence of predominantly 4-substitution by the side chains in each iso-indole residue. Paper chromatography was used to resolve and identify the carboxylic acids, but final confirmation of their identity came from mass spectrometry of the mixture. Nuclear magnetic resonance spectra of the phthalimides produced in high yield during the first stage of oxidation in sulphuric acid by hydrogen peroxide confirmed and extended these findings. The ultra-violet, visible and infra-red spectra of Alcian blue and similar phthalocyanin pigments are discussed, and related to the structure.
A consideration of the possible distributions of four substituents in the eight possible positions which could be substituted leads to the conclusion that Alcian blue 8GX consists mainly of four geometrical isomers, the structures of which are presented.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Bellamy, L.J.: The infra-red spectrum of complex molecules, 2nd ed., chap. 5. London: Methuen & Co. Ltd. 1958.
Bellamy, L.J.: Advances in infra-red group frequencies, p. 50. London: Methuen & Co. Ltd. 1968.
Berezin, B.D.: Izv. Vysshikh. Uchebn. Zavedenii Khimi Khim. Tekhnol. 4, 45 (1961), quoted by Lever, A.B.P. In: The phthalocyanins. Advanc. Inorg. Chem. and Radiochem. 7, 27 (1965).
Bloom, G., Kelly, J.W.: The copper phthalocyanin dye ‘Astrablau’ and its staining properties, especially the staining of mast cells. Histochemie 2, 48–57 (1960).
Ficken, G.E., Linstead, R.P.: Conjugated macrocycles, XXIII. Tetracyclohexenotetrazaporphin. J. chem. Soc. 4846 (1952).
Howard, H.T.: Associate Research Manager, Dyestuffs Division, I.C.I. Ltd. Blackley, Manchester. Letter to the Author, 4th Aug. 1969.
Keen, I.M., Malerbi, B.W.: The preparation and infra-red spectra of phthalocyanin derivatives of the platinum-group metals. J. Inorg. Nucl. Chem. 27, 1311–1319 (1965).
Knudsen, B.I.: Copper phthalocyanin. Infrared absorption spectra of polymorphic modifications. Acta chem. scand. 20, 1344–1350 (1966).
Lillie, R.D.: Conn's biological stains, p. 324, 8th ed. Baltimore: Williams & Wilkins 1969.
Neal, S.M.: Academic Liaison Office, Dyestuffs Division, I.C.I. Ltd. Blackley, Manchester. Letter to the Author, April 2nd, 1963.
Scott, J.E.: Histochemistry of Alcian blue: I. Metachromasia of Alcian blue, Astrablau and other cationic phthalocyanin dyes. Histochemie 21, 277–285 (1970).
Scott, J.E.: Histochemistry of Alcian blue. A note on the presence and removal of boric acid as the major diluent in Alcian blue 8GX. Histochemie 29, 129–133 (1972).
Scott, J.E., Guilford, H.: Alcian blue 8GX: Investigation of structural details using N.M.R. and mass spectrometry. J. Histochem. Cytochem. In the press. (1972).
Scott, J.E., Quintarelli, G., Dellovo, M.C.: The chemical and histochemical properties of Alcian blue. I. The mechanism of Alcian blue staining. Histochemie 4, 73–85 (1964).
Scott, J.E., Tigwell, M. J., Guilford, H.: The composition and structure of Alcian blue 8GX. Proc. roy. micr. Soc. 7, 45–46 (1972).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Scott, J.E. Histochemistry of Alcian blue. Histochemie 30, 215–234 (1972). https://doi.org/10.1007/BF00277593
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF00277593