Eosin Staining of Soft-Tissue Samples: An Eosin-Based Procedure for Whole Mouse Kidney Staining to Visualize Specific Tissue Microstructures

Start by fixating the soft tissue samples. Fill a 50-milliliter centrifuge tube with a fixative solution containing 9.5 milliliters of 4% formaldehyde and 0.5 milliliters of glacial acetic acid. Add the soft tissue sample to the centrifuge tube, and refrigerate it for 24 to 72 hours.

After refrigeration, wash the soft tissue sample with DPBS solution for 1 hour. Then, stain the sample by placing it in 2 milliliters of eosin Y-staining solution, and incubate it on a horizontal shaking plate for 24 hours.

On the next day, carefully take the soft tissue sample out of the sample container and remove excess staining agent with cellulose tissue paper. Place it in a conical container above an ethanol vapor phase for storage and further use.