Schiff reactive is a component of the PAS-Hematoxylin staining protocol. It consists of basic fuchsin (Pararosaniline hydrochloride), chloride acid, and sodium metabisulfite or potassium metabisulfite. Schiff reactive is commonly used for detecting carbohydrates, more precissely by binding to aldehyde groups formed during the staining protocol (see the PAS-hematoxylin staining ↗ ). There are several ways to prepare the Schiff reactive, which can be found in the book "Initiations aux techniques de l'hisotlogie animale" by Martoja and Martoja (1970; Spanish edition, Toray-Masson).
Prodecures
Coleman method
200 ml of boiling distilled water.
1 g basic fuchsin (Pararosaniline hydrochloride)
Cool the solution
2 g potassium metabisulfite or sodium metabisulfite
10 ml chloride acid
After 24 hours, add:
0.5 g active carbon
Stir vigorously for 1 min, let it rest, and then filter.
Lillie method
1 g basic fuchsin (Pararosaniline hydrochloride)
1.9 g potassium metabisulfite or sodium metabisulfite
100 ml of 0.15 N chloride acid
Leave the solution to be de-colorized, and agitate it from time to time. When the color is almost gone (12-24h), continue with the procedure.
0.5 g active carbon
Stir vigorously for 1 min, let it rest, and then filter.
Graumann method
0.5 g basic fuchsin (Pararosaniline hydrochloride)
0.5 g potassium metabisulfite or sodium metabisulfite
15 ml of 1 N chloride acid
85 ml distilled water
Mix the solution and let it rest for 24 h. When the color fades away, continue with the procedure.
0.5 g active carbon
Stir vigorously for 1 min, let it rest, and then filter.
Notes
Whatever the method, the final solution has to be kept in darkness in a tightly sealed bottle. It is a good idea to store it in a refrigerator. Before use, check if the solution smells like sulfurous. If it is not, add a drop of chloride acid and a bit (a few decigrams) of sodium (or potassium) metabisulfite.
Products
Basic fuchsin (Pararosaniline hydrochloride)
Sodium metabisulfite
Potassium metabisulfite
Chloride acid
Active carbon
Distilled water
Labware
Test tube
Balance
Magnetic stirrer/hot plate
Flasks
Bottles
Dark envelopes
Refrigerator