Phosphate-Buffered 4% Paraformaldehyde with Picric Acid
This filtered and ready-to-use tissue fixative is freshly made with high purity paraformaldehyde powder and saturated picric acid solution according to Zamboni and de Martino¹. This fixative has been proven to preserve generally better morphology and antigenicity compared to the phosphate-buffered 4% paraformaldehyde. This fixative may be stored at room temperature for at least one year without change of the original quality.
Reference: Zamboni L. and de Martino C. (1967) J. Cell Biol. 35:148.