(also used for primary and secondary antibody incubation steps)
1x PBS (1 mM Ca2+, 1 mM Mg2+), pH 7.4
+ 0.2% saponin
+5% normal donkey serum (or goat, depending on secondary antibody species)
Dissolve by stirring or gentle vortexing. Filter sterilize and store aliquots at -20°C.
For permeabilization step, supplement the above with 0.1-0.3% Triton X-100.
4% formaldehyde solution for fixing cells
- Dissolve 4g paraformaldehyde in 80ml H2O in a fume hood
- Heat to 60 °C (approximately) on a hot plate with stirring until mostly dissolved; add a few drops of NaOH to help dissolve
- Cool to room temperature
- Add 10 ml 10x PBS (no Ca2+, Mg2+)
- Filter with a 0.22 µM disposable syringe filter