Add the following amounts of magnesium chloride to the alcian blue solution to obtain the electrolyte molarity noted. Prepare fresh.
5µ paraffin sections of neutral buffered formalin fixed tissue are suitable.
Bring sections to water via xylene and ethanol.
Place a section into each alcian blue electrolyte concentration chosen and leave overnight.
Wash with water.
Counterstain with neutral red, if wished.
Dehydrate with ethanols.
Clear with xylene and mount with a resinous medium.
Expected results Electrolyte concentration
0.06M 0.2M–0.3M 0.5M–0.6M 0.7M–0.8M 0.9M Nuclei
All acid mucopolysaccharides Sulphated acid mucopolysaccharides Strongly sulphated acid mucopolysaccharides Heparin, heparan sulphate, keratan sulphate Keratan sulphate Red, if counterstained
Blue Blue Blue Blue Blue
The amounts given for magnesium chloride are based on a formula weight of 203.3 for the hexahydrate.
If the salt used is other other than this, adjust the amounts added to each solution to obtain the correct molarity.
Magnesium chloride is hygroscopic. Store appropriately.
The electrolyte molarities for each mucopolysaccharide are not considered absolutes, and
personal standardising and evaluation are required.
This method is usually explained on the basis of magnesium ions competing with alcian blue
for binding sites on mucopolysaccharides. As the concentration of magnesium ions increases, so more binding
sites are blocked from access to alcian blue.
Reference Bancroft, J.D. and Stevens A. (1982) Theory and practice of histological techniques Ed. 2
Churchill Livingstone, Edinburgh & London, UK.