The eosin-phloxin solution in acetic acid alcohol is a staining solution used in histology and cytology for staining cell structures. This solution contains the two stains eosin and phloxin dissolved in a mixture of ethanol and acetic acid.

Eosin is an acidic dye that has a marked affinity for basic tissue components, including proteins, hemoglobin and muscle proteins. It produces a distinctive red hue and provides excellent contrast of cellular structures.

Phloxin is also an acidic dye and binds primarily to basic structures such as cell nuclei and nucleic acids. The intense staining produced by phloxin allows clear delineation of cell nuclei and aids in the precise identification of different cell types.

The use of acetic acid alcohol as a solvent offers certain advantages. It enables rapid and uniform staining and ensures optimal distribution of dyes. In addition, the acidic environment of acetic acid can help to enhance and stabilize the binding of the dyes to the target structures.