Picrosirius Red Staining

Picrosirius Red Staining

To make the Picrosirius stain

- Make saturated aqueous picric acid : heat 2~3 heaping teaspoons picric acid in 500+ ml distilled water, then cool. We use a magnetic stirrer / hot plate. If yellow needle-like crystals are not present when cool, then temperature was not high enough, or more acid is needed. Try heating again. Note : dry picric acid not in solution is very dangerous (combustible), so keep wet! Drain liquid for stain ; crystals may be used again.

- Add 0.1 gram sirius red F3BA per 100ml.
- Allow solution to stand for 24 hours.
- Stain should keep for a few months at room temperature, or 100 slides, whichever comes first.
- 250 ml are needed for  proper staining procedure.


Staining : 

- Paraffin embedded, 5 or 10 um thick sections are stained as follows:

Histoclear #1 - 3 minutes
Histoclear #2 - 3 minutes
Histoclear #3 - 3 minutes
100% EtOH - 3 minutes
95% EtOH - 3 minutes
70% EtOH - 3 minutes
H2O Rinse - 10 minutes
PS stain - 90 minutes
70% EtOH - 3 minutes
95% EtOH - 3 minutes
100% EtOH - 3 minutes
100% EtOH - 3 minutes
Histoclear #4 - 3 minutes
Histoclear #5 - 3 minutes
Histoclear #6 - 3 minutes

Note : can add 0.2% phosphomolybdic acid in DD H2O for 2 minutes with quick rinse after 10 minute water step above.

Note : In case of freezing section, 
        1) 60°C dry oven 30 min
        2) H2O rinse 10 min
        3) PS stain 90 min
        4) MQ washing