Metachromatic staining and electron dense reaction of glycosaminoglycans by means of cuprolinic blue.
The cationic phthalocyanin-like dye Cuprolinic Blue, unlike phthalocyanin dyes such as Alcian Blue or Astra Blue, can definitely exhibit a clear metachromatic reaction with appropriate substrates. The application of Cuprolinic Blue to epoxy-embedded semithin sections revealed that mast cell cytoplasmic granules, goblet cell mucin and cartilage matrix stained in violet shades (metachromatic), whereas nuclear chromatin presented a bright blue coloration (orthochromatic). The metachromatic structures showed a high degree of contrast when ultrathin sections treated with Cuprolinic Blue were examined by electron microscopy. Cytophotometric measurements of stained components from the large intestine showed different absorption maxima: at 580 nm for mucin and at 640 nm for nuclei. The spectroscopical analysis revealed a clear-cut metachromatic shift when the dye was in the presence of chondroitin-4-sulphate. The addition of aluminium metal to Cuprolinic Blue solutions resulted in a striking spectral change; under such conditions the dye showed absorption maximum at 530 nm.
D000818:Animals; D004396:Coloring Agents; D003594:Cytoplasmic Granules / Q000378:metabolism; D005260:Female; D006025:Glycosaminoglycans / Q000378:metabolism*; D006651:Histocytochemistry; D007211:Indoles; D007413:Intestinal Mucosa / Q000378:metabolism; D008297:Male; D008407:Mast Cells / Q000378:metabolism; D051379:Mice; D009077:Mucins / Q000378:metabolism; D009942:Organometallic Compounds; D051381:Rats; D013053:Spectrophotometry
D004396:Coloring Agents; D006025:Glycosaminoglycans; D007211:Indoles; D009077:Mucins; D009942:Organometallic Compounds; C015445:copper phthalocyanine