Papanicolaou EA65 Stain Solution

The Papanicolaou stain is the gold standard in cytology. Initially developed to assess estrogen levels in vaginal epithelium and to detect pathogens such as Candida and Trichomonas in the genital tract, this method uses a combination of Orange G6 and either EA36 or EA50. This staining protocol produces vivid green, blue, and pink cytoplasmic coloration. Key features include bright, transparent cytoplasm and sharp visualization of nuclear membranes, nucleoli, and chromatin structures. The Pap stain is particularly effective for exfoliated cell specimens, rendering nuclei blue to black while staining the cytoplasm of keratinizing squamous cells pink to orange-red.

As a variant of the Pap stain, the Papanicolaou EA65 Stain Solution is preferred over EA36 and EA50 for staining exfoliated cells from non-gynecological samples.