5µ paraffin sections of neutral buffered formalin fixed tissue are suitable.
Other fixatives are likely to be satisfactory. Cryostat sections usually show brighter metachromasia.
Unmounted frozen sections may also be floated in each solution and mounted on a slide just before coverslipping.
Bring sections to water via xylene and ethanol, except for cryostat and frozen sections.
Stain nuclei with Weigert's iron hematoxylin for 5 minutes.
Wash with water.
Place into crystal violet solution for 1-30 minutes until amyloid is stained.
Rinse well with water.
Drain all water from the slide until just damp and mount with Highman's medium.
Ring the coverslip to inhibit evaporation of the mounting medium and precipitation of the ingredients.
Amyloid – purple-red
Background – Blue-violet
Nuclei – Black
Methyl violet may be used instead of crystal violet if preferred.
Gray notes that Lieb substituted a solution of 0.3% crystal violet in 0.3% hydrochloric acid for Highman's crystal violet solution.
Highman's gum syrup is a modification of Apathy's gum syrup and contains potassium acetate or
sodium chloride to stop bleeding of the dye into the mounting medium.
Reference Gray, Peter. (1954) The Microtomist's Formulary and Guide, p. 452. Originally published by:– The Blakiston Co. Republished by:– Robert E. Krieger Publishing Co.