4% paraformaldehyde in PBS for immunostaining
4.0 g paraformaldehyde (laboratory grade)
Place the PBS and paraformaldehyde in a bottle together, and put the bottle in a water bath set to 70°C-75°C. Swirl the solution occasionally until all of the paraformaldehyde is dissolved (may take a couple of hours). Cool the solution to room temperature, and filter it through a 0.22-μm filter to remove any particulate matter. Store it at 4°C-8°C.
